21595164 has 24 divisors (see below), whose sum is σ = 50574720. Its totient is φ = 7171824.

The previous prime is 21595163. The next prime is 21595187. The reversal of 21595164 is 46159512.

It is a super-2 number, since 2×21595164² = 932702216373792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21595163) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 217 + ... + 6575.

It is an arithmetic number, because the mean of its divisors is an integer number (2107280).

Almost surely, 2^21595164 is an apocalyptic number.

It is an amenable number.

21595164 is an abundant number, since it is smaller than the sum of its proper divisors (28979556).

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

21595164 is a wasteful number, since it uses less digits than its factorization.

21595164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6649 (or 6647 counting only the distinct ones).

The product of its digits is 10800, while the sum is 33.

The square root of 21595164 is about 4647.0597155621. The cubic root of 21595164 is about 278.4745444621.

The spelling of 21595164 in words is "twenty-one million, five hundred ninety-five thousand, one hundred sixty-four".