84890066881 has 3 divisors (see below), whose sum is σ = 84890358241. Its totient is φ = 84889775522.

The previous prime is 84890066869. The next prime is 84890066893. The reversal of 84890066881 is 18866009848.

The square root of 84890066881 is 291359.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (84890066869) and next prime (84890066893).

It is not a de Polignac number, because 84890066881 - 2¹³ = 84890058689 is a prime.

It is a super-2 number, since 2×84890066881² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84890066801) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 145680 + ... + 437038.

Almost surely, 2^84890066881 is an apocalyptic number.

84890066881 is the 291359-th square number.

84890066881 is the 145680-th centered octagonal number.

It is an amenable number.

84890066881 is a deficient number, since it is larger than the sum of its proper divisors (291360).

84890066881 is an frugal number, since it uses more digits than its factorization.

84890066881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582718 (or 291359 counting only the distinct ones).

The product of its (nonzero) digits is 5308416, while the sum is 58.

The spelling of 84890066881 in words is "eighty-four billion, eight hundred ninety million, sixty-six thousand, eight hundred eighty-one".