21606662 has 32 divisors (see below), whose sum is σ = 40690944. Its totient is φ = 8359200.

The previous prime is 21606623. The next prime is 21606671. The reversal of 21606662 is 26660612.

It is a congruent 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, 26237 + ... + 27047.

It is an arithmetic number, because the mean of its divisors is an integer number (1271592).

Almost surely, 2^21606662 is an apocalyptic number.

21606662 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21606662 is a deficient number, since it is larger than the sum of its proper divisors (19084282).

21606662 is a wasteful number, since it uses less digits than its factorization.

21606662 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1004.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 21606662 is about 4648.2966772787. The cubic root of 21606662 is about 278.5239588004.

The spelling of 21606662 in words is "twenty-one million, six hundred six thousand, six hundred sixty-two".