21540700 has 36 divisors (see below), whose sum is σ = 49496832. Its totient is φ = 8108800.

The previous prime is 21540679. The next prime is 21540709. The reversal of 21540700 is 704512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21540709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4636 + ... + 8035.

It is an arithmetic number, because the mean of its divisors is an integer number (1374912).

Almost surely, 2^21540700 is an apocalyptic number.

21540700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21540700 is an abundant number, since it is smaller than the sum of its proper divisors (27956132).

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

21540700 is a wasteful number, since it uses less digits than its factorization.

21540700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12702 (or 12695 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 21540700 is about 4641.1959665586. The cubic root of 21540700 is about 278.2402388251.

The spelling of 21540700 in words is "twenty-one million, five hundred forty thousand, seven hundred".