21107952 has 120 divisors (see below), whose sum is σ = 62964720. Its totient is φ = 6842880.

The previous prime is 21107929. The next prime is 21107953. The reversal of 21107952 is 25970112.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21107953) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 237124 + ... + 237212.

It is an arithmetic number, because the mean of its divisors is an integer number (524706).

Almost surely, 2^21107952 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21107952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31482360).

21107952 is an abundant number, since it is smaller than the sum of its proper divisors (41856768).

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

21107952 is an equidigital number, since it uses as much as digits as its factorization.

21107952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 21107952 is about 4594.3391254891. The cubic root of 21107952 is about 276.3643581048.

The spelling of 21107952 in words is "twenty-one million, one hundred seven thousand, nine hundred fifty-two".