21677164 has 6 divisors (see below), whose sum is σ = 37935044. Its totient is φ = 10838580.

The previous prime is 21677141. The next prime is 21677167. The reversal of 21677164 is 46177612.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21677167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2709642 + ... + 2709649.

Almost surely, 2^21677164 is an apocalyptic number.

It is an amenable number.

21677164 is a deficient number, since it is larger than the sum of its proper divisors (16257880).

21677164 is a wasteful number, since it uses less digits than its factorization.

21677164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5419295 (or 5419293 counting only the distinct ones).

The product of its digits is 14112, while the sum is 34.

The square root of 21677164 is about 4655.8741391923. The cubic root of 21677164 is about 278.8265688160.

The spelling of 21677164 in words is "twenty-one million, six hundred seventy-seven thousand, one hundred sixty-four".