21115156 has 48 divisors (see below), whose sum is σ = 42033600. Its totient is φ = 9220608.

The previous prime is 21115141. The next prime is 21115189. The reversal of 21115156 is 65151112.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76090 + ... + 76366.

It is an arithmetic number, because the mean of its divisors is an integer number (875700).

Almost surely, 2^21115156 is an apocalyptic number.

It is an amenable number.

21115156 is a deficient number, since it is larger than the sum of its proper divisors (20918444).

21115156 is a wasteful number, since it uses less digits than its factorization.

21115156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376 (or 374 counting only the distinct ones).

The product of its digits is 300, while the sum is 22.

The square root of 21115156 is about 4595.1230669047. The cubic root of 21115156 is about 276.3957949520.

Adding to 21115156 its reverse (65151112), we get a palindrome (86266268).

The spelling of 21115156 in words is "twenty-one million, one hundred fifteen thousand, one hundred fifty-six".