21533502525240 has 64 divisors (see below), whose sum is σ = 64820987229600. Its totient is φ = 5722669148672.

The previous prime is 21533502525181. The next prime is 21533502525277. The reversal of 21533502525240 is 4252520533512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 306186435 + ... + 306256754.

Almost surely, 2^{21533502525240} is an apocalyptic number.

21533502525240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21533502525240 is an abundant number, since it is smaller than the sum of its proper divisors (43287484704360).

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

21533502525240 is a wasteful number, since it uses less digits than its factorization.

21533502525240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612443496 (or 612443492 counting only the distinct ones).

The product of its (nonzero) digits is 360000, while the sum is 39.

The spelling of 21533502525240 in words is "twenty-one trillion, five hundred thirty-three billion, five hundred two million, five hundred twenty-five thousand, two hundred forty".