21645714 has 32 divisors (see below), whose sum is σ = 45650304. Its totient is φ = 6828800.

The previous prime is 21645707. The next prime is 21645733. The reversal of 21645714 is 41754612.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13162 + ... + 14714.

It is an arithmetic number, because the mean of its divisors is an integer number (1426572).

Almost surely, 2^21645714 is an apocalyptic number.

21645714 is an abundant number, since it is smaller than the sum of its proper divisors (24004590).

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

21645714 is a wasteful number, since it uses less digits than its factorization.

21645714 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1682.

The product of its digits is 6720, while the sum is 30.

The square root of 21645714 is about 4652.4954594282. The cubic root of 21645714 is about 278.6916597192.

The spelling of 21645714 in words is "twenty-one million, six hundred forty-five thousand, seven hundred fourteen".