21858604 has 6 divisors (see below), whose sum is σ = 38252564. Its totient is φ = 10929300.

The previous prime is 21858581. The next prime is 21858623. The reversal of 21858604 is 40685812.

It is a self number, because there is not a number n which added to its sum of digits gives 21858604.

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 as a sum of consecutive naturals, namely, 2732322 + ... + 2732329.

Almost surely, 2^21858604 is an apocalyptic number.

It is an amenable number.

21858604 is a deficient number, since it is larger than the sum of its proper divisors (16393960).

21858604 is a wasteful number, since it uses less digits than its factorization.

21858604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5464655 (or 5464653 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 21858604 is about 4675.3185987695. The cubic root of 21858604 is about 279.6023436787.

The spelling of 21858604 in words is "twenty-one million, eight hundred fifty-eight thousand, six hundred four".