21533292 has 36 divisors (see below), whose sum is σ = 59380776. Its totient is φ = 6525120.

The previous prime is 21533279. The next prime is 21533293. The reversal of 21533292 is 29233512.

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (21533293) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 26793 + ... + 27584.

It is an arithmetic number, because the mean of its divisors is an integer number (1649466).

Almost surely, 2^21533292 is an apocalyptic number.

21533292 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21533292 is an abundant number, since it is smaller than the sum of its proper divisors (37847484).

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

21533292 is a wasteful number, since it uses less digits than its factorization.

21533292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54398 (or 54393 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 21533292 is about 4640.3978277730. The cubic root of 21533292 is about 278.2083389020.

It can be divided in two parts, 2153 and 3292, that added together give a palindrome (5445).

The spelling of 21533292 in words is "twenty-one million, five hundred thirty-three thousand, two hundred ninety-two".