21948264 has 96 divisors (see below), whose sum is σ = 64864800. Its totient is φ = 6664320.

The previous prime is 21948263. The next prime is 21948293. The reversal of 21948264 is 46284912.

It is a super-2 number, since 2×21948264² = 963452585227392, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21948263) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 122527 + ... + 122705.

It is an arithmetic number, because the mean of its divisors is an integer number (675675).

Almost surely, 2^21948264 is an apocalyptic number.

21948264 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21948264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32432400).

21948264 is an abundant number, since it is smaller than the sum of its proper divisors (42916536).

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

21948264 is a wasteful number, since it uses less digits than its factorization.

21948264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335 (or 328 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 21948264 is about 4684.8974375113. The cubic root of 21948264 is about 279.9841147451.

The spelling of 21948264 in words is "twenty-one million, nine hundred forty-eight thousand, two hundred sixty-four".