21266432 has 64 divisors (see below), whose sum is σ = 47185200. Its totient is φ = 9502720.

The previous prime is 21266411. The next prime is 21266449. The reversal of 21266432 is 23466212.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×21266432² = 904522260021248, which contains 22 as substring.

Its product of digits (3456) is a multiple of the sum of its prime divisors (72).

It is a zygodrome in base 3.

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, 360419 + ... + 360477.

Almost surely, 2^21266432 is an apocalyptic number.

21266432 is a gapful number since it is divisible by the number (22) 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 21266432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23592600).

21266432 is an abundant number, since it is smaller than the sum of its proper divisors (25918768).

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

21266432 is an frugal number, since it uses more digits than its factorization.

21266432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100 (or 72 counting only the distinct ones).

The product of its digits is 3456, while the sum is 26.

The square root of 21266432 is about 4611.5541848709. The cubic root of 21266432 is about 277.0542886899.

It can be divided in two parts, 2126 and 6432, that added together give a palindrome (8558).

The spelling of 21266432 in words is "twenty-one million, two hundred sixty-six thousand, four hundred thirty-two".