21433020 has 48 divisors (see below), whose sum is σ = 68587008. Its totient is φ = 4898880.

The previous prime is 21432991. The next prime is 21433051. The reversal of 21433020 is 2033412.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25096 + ... + 25935.

It is an arithmetic number, because the mean of its divisors is an integer number (1428896).

Almost surely, 2^21433020 is an apocalyptic number.

21433020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21433020 is an abundant number, since it is smaller than the sum of its proper divisors (47153988).

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

21433020 is a wasteful number, since it uses less digits than its factorization.

21433020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51050 (or 51048 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 21433020 is about 4629.5809745591. The cubic root of 21433020 is about 277.7758315715.

Adding to 21433020 its reverse (2033412), we get a palindrome (23466432).

The spelling of 21433020 in words is "twenty-one million, four hundred thirty-three thousand, twenty".