21540675 has 24 divisors (see below), whose sum is σ = 38355184. Its totient is φ = 10604160.

The previous prime is 21540653. The next prime is 21540677. The reversal of 21540675 is 57604512.

It is not a de Polignac number, because 21540675 - 2⁶ = 21540611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21540677) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10072 + ... + 12021.

Almost surely, 2^21540675 is an apocalyptic number.

21540675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21540675 is a deficient number, since it is larger than the sum of its proper divisors (16814509).

21540675 is a wasteful number, since it uses less digits than its factorization.

21540675 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22119 (or 22114 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 30.

The square root of 21540675 is about 4641.1932732865. The cubic root of 21540675 is about 278.2401311838.

The spelling of 21540675 in words is "twenty-one million, five hundred forty thousand, six hundred seventy-five".