21641416 has 16 divisors (see below), whose sum is σ = 40758300. Its totient is φ = 10772544.

The previous prime is 21641393. The next prime is 21641467. The reversal of 21641416 is 61414612.

It can be written as a sum of positive squares in 2 ways, for example, as 20738916 + 902500 = 4554^2 + 950^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4075 + ... + 7738.

Almost surely, 2^21641416 is an apocalyptic number.

It is an amenable number.

21641416 is a deficient number, since it is larger than the sum of its proper divisors (19116884).

21641416 is a wasteful number, since it uses less digits than its factorization.

21641416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12048 (or 12044 counting only the distinct ones).

The product of its digits is 1152, while the sum is 25.

The square root of 21641416 is about 4652.0335338430. The cubic root of 21641416 is about 278.6732127102.

The spelling of 21641416 in words is "twenty-one million, six hundred forty-one thousand, four hundred sixteen".