21535501460 has 48 divisors (see below), whose sum is σ = 50669297280. Its totient is φ = 7619437440.

The previous prime is 21535501409. The next prime is 21535501469. The reversal of 21535501460 is 6410553512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21535501469) 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, 1314680 + ... + 1330959.

It is an arithmetic number, because the mean of its divisors is an integer number (1055610360).

Almost surely, 2^21535501460 is an apocalyptic number.

21535501460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21535501460 is an abundant number, since it is smaller than the sum of its proper divisors (29133795820).

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

21535501460 is a wasteful number, since it uses less digits than its factorization.

21535501460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2645696 (or 2645694 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 32.

The spelling of 21535501460 in words is "twenty-one billion, five hundred thirty-five million, five hundred one thousand, four hundred sixty".