9539664981 has 16 divisors (see below), whose sum is σ = 15858144768. Its totient is φ = 4955670000.

The previous prime is 9539664977. The next prime is 9539664991. The reversal of 9539664981 is 1894669359.

It is not a de Polignac number, because 9539664981 - 2² = 9539664977 is a prime.

It is a super-2 number, since 2×9539664981² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9539664961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20648395 + ... + 20648856.

It is an arithmetic number, because the mean of its divisors is an integer number (991134048).

Almost surely, 2^9539664981 is an apocalyptic number.

It is an amenable number.

9539664981 is a deficient number, since it is larger than the sum of its proper divisors (6318479787).

9539664981 is a wasteful number, since it uses less digits than its factorization.

9539664981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41297272.

The product of its digits is 12597120, while the sum is 60.

The square root of 9539664981 is about 97671.2085570768. The cubic root of 9539664981 is about 2120.8553108812.

The spelling of 9539664981 in words is "nine billion, five hundred thirty-nine million, six hundred sixty-four thousand, nine hundred eighty-one".