21525104540 has 24 divisors (see below), whose sum is σ = 47861703792. Its totient is φ = 8103568640.

The previous prime is 21525104477. The next prime is 21525104593. The reversal of 21525104540 is 4540152512.

It is a super-2 number, since 2×21525104540² (a number of 21 digits) contains 22 as substring.

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, 31654226 + ... + 31654905.

It is an arithmetic number, because the mean of its divisors is an integer number (1994237658).

Almost surely, 2^21525104540 is an apocalyptic number.

21525104540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21525104540 is an abundant number, since it is smaller than the sum of its proper divisors (26336599252).

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

21525104540 is a wasteful number, since it uses less digits than its factorization.

21525104540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63309157 (or 63309155 counting only the distinct ones).

The product of its (nonzero) digits is 8000, while the sum is 29.

The spelling of 21525104540 in words is "twenty-one billion, five hundred twenty-five million, one hundred four thousand, five hundred forty".