21435264 has 96 divisors (see below), whose sum is σ = 64443600. Its totient is φ = 6825984.

The previous prime is 21435259. The next prime is 21435299. The reversal of 21435264 is 46253412.

It is a tau number, because it is divible by the number of its divisors (96).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 26092 + ... + 26900.

Almost surely, 2^21435264 is an apocalyptic number.

21435264 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 21435264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32221800).

21435264 is an abundant number, since it is smaller than the sum of its proper divisors (43008336).

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

21435264 is a wasteful number, since it uses less digits than its factorization.

21435264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 852 (or 837 counting only the distinct ones).

The product of its digits is 5760, while the sum is 27.

The square root of 21435264 is about 4629.8233227630. The cubic root of 21435264 is about 277.7855254491.

Adding to 21435264 its reverse (46253412), we get a palindrome (67688676).

The spelling of 21435264 in words is "twenty-one million, four hundred thirty-five thousand, two hundred sixty-four".