21274824 has 32 divisors (see below), whose sum is σ = 53424000. Its totient is φ = 7060032.

The previous prime is 21274823. The next prime is 21274829. The reversal of 21274824 is 42847212.

It is a junction number, because it is equal to n+sod(n) for n = 21274791 and 21274800.

It is not an unprimeable number, because it can be changed into a prime (21274823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3882 + ... + 7590.

It is an arithmetic number, because the mean of its divisors is an integer number (1669500).

Almost surely, 2^21274824 is an apocalyptic number.

21274824 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21274824 is an abundant number, since it is smaller than the sum of its proper divisors (32149176).

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

21274824 is a wasteful number, since it uses less digits than its factorization.

21274824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3957 (or 3953 counting only the distinct ones).

The product of its digits is 7168, while the sum is 30.

The square root of 21274824 is about 4612.4639835992. The cubic root of 21274824 is about 277.0907269263.

The spelling of 21274824 in words is "twenty-one million, two hundred seventy-four thousand, eight hundred twenty-four".