21677704 has 8 divisors (see below), whose sum is σ = 40645710. Its totient is φ = 10838848.

The previous prime is 21677701. The next prime is 21677713. The reversal of 21677704 is 40777612.

It can be written as a sum of positive squares in only one way, i.e., 16793604 + 4884100 = 4098^2 + 2210^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 21677704.

It is not an unprimeable number, because it can be changed into a prime (21677701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1354849 + ... + 1354864.

Almost surely, 2^21677704 is an apocalyptic number.

It is an amenable number.

21677704 is a deficient number, since it is larger than the sum of its proper divisors (18968006).

21677704 is a wasteful number, since it uses less digits than its factorization.

21677704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2709719 (or 2709715 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 34.

The square root of 21677704 is about 4655.9321300895. The cubic root of 21677704 is about 278.8288840804.

The spelling of 21677704 in words is "twenty-one million, six hundred seventy-seven thousand, seven hundred four".