21364474 has 16 divisors (see below), whose sum is σ = 34898400. Its totient is φ = 9770544.

The previous prime is 21364471. The next prime is 21364481. The reversal of 21364474 is 47446312.

It is not an unprimeable number, because it can be changed into a prime (21364471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8592 + ... + 10795.

It is an arithmetic number, because the mean of its divisors is an integer number (2181150).

Almost surely, 2^21364474 is an apocalyptic number.

21364474 is a deficient number, since it is larger than the sum of its proper divisors (13533926).

21364474 is a wasteful number, since it uses less digits than its factorization.

21364474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19437.

The product of its digits is 16128, while the sum is 31.

The square root of 21364474 is about 4622.1720002613. The cubic root of 21364474 is about 277.4793924583.

The spelling of 21364474 in words is "twenty-one million, three hundred sixty-four thousand, four hundred seventy-four".