21415164 has 24 divisors (see below), whose sum is σ = 50193360. Its totient is φ = 7106304.

The previous prime is 21415159. The next prime is 21415181. The reversal of 21415164 is 46151412.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1149 + ... + 6644.

It is an arithmetic number, because the mean of its divisors is an integer number (2091390).

Almost surely, 2^21415164 is an apocalyptic number.

It is an amenable number.

21415164 is an abundant number, since it is smaller than the sum of its proper divisors (28778196).

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

21415164 is a wasteful number, since it uses less digits than its factorization.

21415164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8029 (or 8027 counting only the distinct ones).

The product of its digits is 960, while the sum is 24.

The square root of 21415164 is about 4627.6521044694. The cubic root of 21415164 is about 277.6986711390.

Adding to 21415164 its reverse (46151412), we get a palindrome (67566576).

The spelling of 21415164 in words is "twenty-one million, four hundred fifteen thousand, one hundred sixty-four".