21542608 has 20 divisors (see below), whose sum is σ = 41847520. Its totient is φ = 10743264.

The previous prime is 21542597. The next prime is 21542623. The reversal of 21542608 is 80624512.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5491 + ... + 8557.

It is an arithmetic number, because the mean of its divisors is an integer number (2092376).

Almost surely, 2^21542608 is an apocalyptic number.

It is an amenable number.

21542608 is a deficient number, since it is larger than the sum of its proper divisors (20304912).

21542608 is a wasteful number, since it uses less digits than its factorization.

21542608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3514 (or 3508 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 21542608 is about 4641.4015124744. The cubic root of 21542608 is about 278.2484537655.

The spelling of 21542608 in words is "twenty-one million, five hundred forty-two thousand, six hundred eight".