21430618 has 32 divisors (see below), whose sum is σ = 37521792. Its totient is φ = 9081600.

The previous prime is 21430597. The next prime is 21430621. The reversal of 21430618 is 81603412.

It is a junction number, because it is equal to n+sod(n) for n = 21430592 and 21430601.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20230 + ... + 21262.

It is an arithmetic number, because the mean of its divisors is an integer number (1172556).

Almost surely, 2^21430618 is an apocalyptic number.

21430618 is a deficient number, since it is larger than the sum of its proper divisors (16091174).

21430618 is a wasteful number, since it uses less digits than its factorization.

21430618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1110.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 21430618 is about 4629.3215485641. The cubic root of 21430618 is about 277.7654543985.

The spelling of 21430618 in words is "twenty-one million, four hundred thirty thousand, six hundred eighteen".