21442604 has 24 divisors (see below), whose sum is σ = 38201856. Its totient is φ = 10530000.

The previous prime is 21442591. The next prime is 21442637. The reversal of 21442604 is 40624412.

It is a self number, because there is not a number n which added to its sum of digits gives 21442604.

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, 78989 + ... + 79259.

It is an arithmetic number, because the mean of its divisors is an integer number (1591744).

Almost surely, 2^21442604 is an apocalyptic number.

It is an amenable number.

21442604 is a deficient number, since it is larger than the sum of its proper divisors (16759252).

21442604 is a wasteful number, since it uses less digits than its factorization.

21442604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557 (or 555 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

The square root of 21442604 is about 4630.6159417512. The cubic root of 21442604 is about 277.8172288619.

The spelling of 21442604 in words is "twenty-one million, four hundred forty-two thousand, six hundred four".