1610787566881 has 4 divisors (see below), whose sum is σ = 1611141668500. Its totient is φ = 1610433465264.

The previous prime is 1610787566873. The next prime is 1610787566903. The reversal of 1610787566881 is 1886657870161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1477355166225 + 133432400656 = 1215465^2 + 365284^2 .

It is a cyclic number.

It is not a de Polignac number, because 1610787566881 - 2³ = 1610787566873 is a prime.

It is a super-2 number, since 2×1610787566881² (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 (1610787566831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177043986 + ... + 177053083.

It is an arithmetic number, because the mean of its divisors is an integer number (402785417125).

Almost surely, 2^{1610787566881} is an apocalyptic number.

It is an amenable number.

1610787566881 is a deficient number, since it is larger than the sum of its proper divisors (354101619).

1610787566881 is an equidigital number, since it uses as much as digits as its factorization.

1610787566881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354101618.

The product of its (nonzero) digits is 27095040, while the sum is 64.

The spelling of 1610787566881 in words is "one trillion, six hundred ten billion, seven hundred eighty-seven million, five hundred sixty-six thousand, eight hundred eighty-one".