21318152 has 32 divisors (see below), whose sum is σ = 42420000. Its totient is φ = 10015488.

The previous prime is 21318149. The next prime is 21318181. The reversal of 21318152 is 25181312.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20624 + ... + 21632.

It is an arithmetic number, because the mean of its divisors is an integer number (1325625).

Almost surely, 2^21318152 is an apocalyptic number.

It is an amenable number.

21318152 is a deficient number, since it is larger than the sum of its proper divisors (21101848).

21318152 is a wasteful number, since it uses less digits than its factorization.

21318152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1173 (or 1169 counting only the distinct ones).

The product of its digits is 480, while the sum is 23.

The square root of 21318152 is about 4617.1584334956. The cubic root of 21318152 is about 277.2787056996.

Adding to 21318152 its reverse (25181312), we get a palindrome (46499464).

The spelling of 21318152 in words is "twenty-one million, three hundred eighteen thousand, one hundred fifty-two".