21542523500 has 24 divisors (see below), whose sum is σ = 47048872416. Its totient is φ = 8617009200.

The previous prime is 21542523481. The next prime is 21542523547. The reversal of 21542523500 is 532524512.

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, 21542024 + ... + 21543023.

It is an arithmetic number, because the mean of its divisors is an integer number (1960369684).

Almost surely, 2^21542523500 is an apocalyptic number.

21542523500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21542523500 is an abundant number, since it is smaller than the sum of its proper divisors (25506348916).

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

21542523500 is a wasteful number, since it uses less digits than its factorization.

21542523500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43085066 (or 43085054 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 29.

The spelling of 21542523500 in words is "twenty-one billion, five hundred forty-two million, five hundred twenty-three thousand, five hundred".