21706374 has 16 divisors (see below), whose sum is σ = 43610112. Its totient is φ = 7202568.

The previous prime is 21706361. The next prime is 21706381. The reversal of 21706374 is 47360712.

21706374 = T₃₂₅ + T₃₂₆ + ... + T₅₄₇.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6774 + ... + 9449.

It is an arithmetic number, because the mean of its divisors is an integer number (2725632).

Almost surely, 2^21706374 is an apocalyptic number.

21706374 is an abundant number, since it is smaller than the sum of its proper divisors (21903738).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21706374 is a wasteful number, since it uses less digits than its factorization.

21706374 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16451.

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 21706374 is about 4659.0099806719. The cubic root of 21706374 is about 278.9517522972.

The spelling of 21706374 in words is "twenty-one million, seven hundred six thousand, three hundred seventy-four".