21676608 has 42 divisors (see below), whose sum is σ = 62133734. Its totient is φ = 7225344.

The previous prime is 21676607. The next prime is 21676619. The reversal of 21676608 is 80667612.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16257024 + 5419584 = 4032^2 + 2328^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21676607) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18241 + ... + 19392.

Almost surely, 2^21676608 is an apocalyptic number.

It is an amenable number.

21676608 is an abundant number, since it is smaller than the sum of its proper divisors (40457126).

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

21676608 is a wasteful number, since it uses less digits than its factorization.

21676608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37651 (or 37638 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 21676608 is about 4655.8144292916. The cubic root of 21676608 is about 278.8241849110.

The spelling of 21676608 in words is "twenty-one million, six hundred seventy-six thousand, six hundred eight".