21312994 has 8 divisors (see below), whose sum is σ = 32091840. Its totient is φ = 10615716.

The previous prime is 21312979. The next prime is 21313001. The reversal of 21312994 is 49921312.

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, 19734 + ... + 20785.

It is an arithmetic number, because the mean of its divisors is an integer number (4011480).

Almost surely, 2^21312994 is an apocalyptic number.

21312994 is a deficient number, since it is larger than the sum of its proper divisors (10778846).

21312994 is a wasteful number, since it uses less digits than its factorization.

21312994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40784.

The product of its digits is 3888, while the sum is 31.

The square root of 21312994 is about 4616.5998310445. The cubic root of 21312994 is about 277.2563410511.

The spelling of 21312994 in words is "twenty-one million, three hundred twelve thousand, nine hundred ninety-four".