981557131 has 4 divisors (see below), whose sum is σ = 1024233552. Its totient is φ = 938880712.

The previous prime is 981557107. The next prime is 981557141. The reversal of 981557131 is 131755189.

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

It is a cyclic number.

It is not a de Polignac number, because 981557131 - 2²⁷ = 847339403 is a prime.

It is a super-2 number, since 2×981557131² = 1926908802833902322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981557141) 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, 21338176 + ... + 21338221.

It is an arithmetic number, because the mean of its divisors is an integer number (256058388).

Almost surely, 2^981557131 is an apocalyptic number.

981557131 is a deficient number, since it is larger than the sum of its proper divisors (42676421).

981557131 is a wasteful number, since it uses less digits than its factorization.

981557131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42676420.

The product of its digits is 37800, while the sum is 40.

The square root of 981557131 is about 31329.8121762643. The cubic root of 981557131 is about 993.8141916737.

The spelling of 981557131 in words is "nine hundred eighty-one million, five hundred fifty-seven thousand, one hundred thirty-one".