21157376 has 60 divisors (see below), whose sum is σ = 44696916. Its totient is φ = 9999360.

The previous prime is 21157373. The next prime is 21157387. The reversal of 21157376 is 67375112.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21157373) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 492011 + ... + 492053.

Almost surely, 2^21157376 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21157376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22348458).

21157376 is an abundant number, since it is smaller than the sum of its proper divisors (23539540).

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

21157376 is an frugal number, since it uses more digits than its factorization.

21157376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 76 counting only the distinct ones).

The product of its digits is 8820, while the sum is 32.

The square root of 21157376 is about 4599.7147737659. The cubic root of 21157376 is about 276.5798911744.

The spelling of 21157376 in words is "twenty-one million, one hundred fifty-seven thousand, three hundred seventy-six".