21933740 has 48 divisors (see below), whose sum is σ = 50367744. Its totient is φ = 7987200.

The previous prime is 21933739. The next prime is 21933767. The reversal of 21933740 is 4733912.

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, 9500 + ... + 11580.

It is an arithmetic number, because the mean of its divisors is an integer number (1049328).

Almost surely, 2^21933740 is an apocalyptic number.

21933740 is a gapful number since it is divisible by the number (20) 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 21933740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25183872).

21933740 is an abundant number, since it is smaller than the sum of its proper divisors (28434004).

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

21933740 is a wasteful number, since it uses less digits than its factorization.

21933740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2138 (or 2136 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 29.

The square root of 21933740 is about 4683.3470936927. The cubic root of 21933740 is about 279.9223424094.

The spelling of 21933740 in words is "twenty-one million, nine hundred thirty-three thousand, seven hundred forty".