21905374 has 4 divisors (see below), whose sum is σ = 32858064. Its totient is φ = 10952686.

The previous prime is 21905339. The next prime is 21905383. The reversal of 21905374 is 47350912.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5476342 + ... + 5476345.

It is an arithmetic number, because the mean of its divisors is an integer number (8214516).

Almost surely, 2^21905374 is an apocalyptic number.

21905374 is a deficient number, since it is larger than the sum of its proper divisors (10952690).

21905374 is a wasteful number, since it uses less digits than its factorization.

21905374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10952689.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 21905374 is about 4680.3177242576. The cubic root of 21905374 is about 279.8016196846.

The spelling of 21905374 in words is "twenty-one million, nine hundred five thousand, three hundred seventy-four".