21540235960 has 32 divisors (see below), whose sum is σ = 49592640240. Its totient is φ = 8415719424.

The previous prime is 21540235957. The next prime is 21540235967. The reversal of 21540235960 is 6953204512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21540235967) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6259977 + ... + 6263416.

Almost surely, 2^21540235960 is an apocalyptic number.

21540235960 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21540235960 is an abundant number, since it is smaller than the sum of its proper divisors (28052404280).

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

21540235960 is a wasteful number, since it uses less digits than its factorization.

21540235960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12523447 (or 12523443 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 37.

The spelling of 21540235960 in words is "twenty-one billion, five hundred forty million, two hundred thirty-five thousand, nine hundred sixty".