1016787872881 has 45 divisors (see below), whose sum is σ = 1168258584423. Its totient is φ = 884290508640.

The previous prime is 1016787872839. The next prime is 1016787872923. The reversal of 1016787872881 is 1882787876101.

It is a happy number.

The square root of 1016787872881 is 1008359.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (1016787872839) and next prime (1016787872923).

It can be written as a sum of positive squares in 7 ways, for example, as 263537462881 + 753250410000 = 513359^2 + 867900^2 .

It is not a de Polignac number, because 1016787872881 - 2³³ = 1008197938289 is a prime.

It is a super-2 number, since 2×1016787872881² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1016787872081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 9328329055 + ... + 9328329163.

Almost surely, 2^{1016787872881} is an apocalyptic number.

1016787872881 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1016787872881 is the 1008359-th square number.

1016787872881 is the 504180-th centered octagonal number.

It is an amenable number.

1016787872881 is a deficient number, since it is larger than the sum of its proper divisors (151470711542).

1016787872881 is an frugal number, since it uses more digits than its factorization.

1016787872881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 16859136, while the sum is 64.

Multiplying 1016787872881 by its sum of digits (64), we get a square (65074423864384 = 8066872²).

The spelling of 1016787872881 in words is "one trillion, sixteen billion, seven hundred eighty-seven million, eight hundred seventy-two thousand, eight hundred eighty-one".