28930638981 has 32 divisors (see below), whose sum is σ = 41870304000. Its totient is φ = 17696747520.

The previous prime is 28930638977. The next prime is 28930638983. The reversal of 28930638981 is 18983603982.

It is not a de Polignac number, because 28930638981 - 2² = 28930638977 is a prime.

It is a super-2 number, since 2×28930638981² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28930638983) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3360120 + ... + 3368718.

It is an arithmetic number, because the mean of its divisors is an integer number (1308447000).

Almost surely, 2^28930638981 is an apocalyptic number.

It is an amenable number.

28930638981 is a deficient number, since it is larger than the sum of its proper divisors (12939665019).

28930638981 is a wasteful number, since it uses less digits than its factorization.

28930638981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10269.

The product of its (nonzero) digits is 4478976, while the sum is 57.

The spelling of 28930638981 in words is "twenty-eight billion, nine hundred thirty million, six hundred thirty-eight thousand, nine hundred eighty-one".