21374951 has 12 divisors (see below), whose sum is σ = 23453280. Its totient is φ = 19468800.

The previous prime is 21374929. The next prime is 21374957. The reversal of 21374951 is 15947312.

It is not a de Polignac number, because 21374951 - 2⁶ = 21374887 is a prime.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21374957) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12551 + ... + 14151.

It is an arithmetic number, because the mean of its divisors is an integer number (1954440).

Almost surely, 2^21374951 is an apocalyptic number.

21374951 is a deficient number, since it is larger than the sum of its proper divisors (2078329).

21374951 is a wasteful number, since it uses less digits than its factorization.

21374951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1706 (or 1693 counting only the distinct ones).

The product of its digits is 7560, while the sum is 32.

The square root of 21374951 is about 4623.3052029906. The cubic root of 21374951 is about 277.5247430796.

The spelling of 21374951 in words is "twenty-one million, three hundred seventy-four thousand, nine hundred fifty-one".