21735264 has 24 divisors (see below), whose sum is σ = 57055320. Its totient is φ = 7245056.

The previous prime is 21735257. The next prime is 21735283. The reversal of 21735264 is 46253712.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×21735264² = 944843402299392, which contains 22 as substring.

It is a congruent number.

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, 113109 + ... + 113300.

It is an arithmetic number, because the mean of its divisors is an integer number (2377305).

Almost surely, 2^21735264 is an apocalyptic number.

21735264 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21735264 is an abundant number, since it is smaller than the sum of its proper divisors (35320056).

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

21735264 is a wasteful number, since it uses less digits than its factorization.

21735264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226422 (or 226414 counting only the distinct ones).

The product of its digits is 10080, while the sum is 30.

The square root of 21735264 is about 4662.1093938259. The cubic root of 21735264 is about 279.0754539565.

Adding to 21735264 its reverse (46253712), we get a palindrome (67988976).

The spelling of 21735264 in words is "twenty-one million, seven hundred thirty-five thousand, two hundred sixty-four".