21933660 has 48 divisors (see below), whose sum is σ = 70189056. Its totient is φ = 5013312.

The previous prime is 21933649. The next prime is 21933671. The reversal of 21933660 is 6633912.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21933649) and next prime (21933671).

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 25692 + ... + 26531.

It is an arithmetic number, because the mean of its divisors is an integer number (1462272).

Almost surely, 2^21933660 is an apocalyptic number.

21933660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21933660 is an abundant number, since it is smaller than the sum of its proper divisors (48255396).

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

21933660 is a wasteful number, since it uses less digits than its factorization.

21933660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52242 (or 52240 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 30.

The square root of 21933660 is about 4683.3385527848. The cubic root of 21933660 is about 279.9220020841.

The spelling of 21933660 in words is "twenty-one million, nine hundred thirty-three thousand, six hundred sixty".