21905156604 has 24 divisors (see below), whose sum is σ = 51256835280. Its totient is φ = 7281032704.

The previous prime is 21905156597. The next prime is 21905156617. The reversal of 21905156604 is 40665150912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2581359 + ... + 2589830.

It is an arithmetic number, because the mean of its divisors is an integer number (2135701470).

Almost surely, 2^21905156604 is an apocalyptic number.

It is an amenable number.

21905156604 is an abundant number, since it is smaller than the sum of its proper divisors (29351678676).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21905156604 is a wasteful number, since it uses less digits than its factorization.

21905156604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5171549 (or 5171547 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 39.

The spelling of 21905156604 in words is "twenty-one billion, nine hundred five million, one hundred fifty-six thousand, six hundred four".