21135394 has 16 divisors (see below), whose sum is σ = 36586368. Its totient is φ = 8969472.

The previous prime is 21135371. The next prime is 21135419. The reversal of 21135394 is 49353112.

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, 5887 + ... + 8770.

It is an arithmetic number, because the mean of its divisors is an integer number (2286648).

Almost surely, 2^21135394 is an apocalyptic number.

21135394 is a deficient number, since it is larger than the sum of its proper divisors (15450974).

21135394 is a wasteful number, since it uses less digits than its factorization.

21135394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14769.

The product of its digits is 3240, while the sum is 28.

The square root of 21135394 is about 4597.3246567977. The cubic root of 21135394 is about 276.4840713846.

The spelling of 21135394 in words is "twenty-one million, one hundred thirty-five thousand, three hundred ninety-four".