21132748 has 24 divisors (see below), whose sum is σ = 45517472. Its totient is φ = 8360064.

The previous prime is 21132739. The next prime is 21132757. The reversal of 21132748 is 84723112.

It is an interprime number because it is at equal distance from previous prime (21132739) and next prime (21132757).

It is a Harshad number since it is a multiple of its sum of digits (28).

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, 28665 + ... + 29392.

Almost surely, 2^21132748 is an apocalyptic number.

21132748 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21132748 is an abundant number, since it is smaller than the sum of its proper divisors (24384724).

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

21132748 is a wasteful number, since it uses less digits than its factorization.

21132748 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58081 (or 58079 counting only the distinct ones).

The product of its digits is 2688, while the sum is 28.

The square root of 21132748 is about 4597.0368717251. The cubic root of 21132748 is about 276.4725329610.

The spelling of 21132748 in words is "twenty-one million, one hundred thirty-two thousand, seven hundred forty-eight".