21394394 has 8 divisors (see below), whose sum is σ = 36676128. Its totient is φ = 9169020.

The previous prime is 21394379. The next prime is 21394427. The reversal of 21394394 is 49349312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 764072 + ... + 764099.

It is an arithmetic number, because the mean of its divisors is an integer number (4584516).

Almost surely, 2^21394394 is an apocalyptic number.

21394394 is a deficient number, since it is larger than the sum of its proper divisors (15281734).

21394394 is a wasteful number, since it uses less digits than its factorization.

21394394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1528180.

The product of its digits is 23328, while the sum is 35.

The square root of 21394394 is about 4625.4074415126. The cubic root of 21394394 is about 277.6088645720.

The spelling of 21394394 in words is "twenty-one million, three hundred ninety-four thousand, three hundred ninety-four".