21153316 has 12 divisors (see below), whose sum is σ = 37378432. Its totient is φ = 10473768.

The previous prime is 21153299. The next prime is 21153323. The reversal of 21153316 is 61335112.

It is a happy number.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25260 + ... + 26083.

Almost surely, 2^21153316 is an apocalyptic number.

It is an amenable number.

21153316 is a deficient number, since it is larger than the sum of its proper divisors (16225116).

21153316 is a wasteful number, since it uses less digits than its factorization.

21153316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51450 (or 51448 counting only the distinct ones).

The product of its digits is 540, while the sum is 22.

The square root of 21153316 is about 4599.2734208786. The cubic root of 21153316 is about 276.5621985867.

Adding to 21153316 its reverse (61335112), we get a palindrome (82488428).

The spelling of 21153316 in words is "twenty-one million, one hundred fifty-three thousand, three hundred sixteen".