21919752 has 48 divisors (see below), whose sum is σ = 59754240. Its totient is φ = 7258848.

The previous prime is 21919741. The next prime is 21919753. The reversal of 21919752 is 25791912.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21919753) 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, 11113 + ... + 12935.

It is an arithmetic number, because the mean of its divisors is an integer number (1244880).

Almost surely, 2^21919752 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 21919752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29877120).

21919752 is an abundant number, since it is smaller than the sum of its proper divisors (37834488).

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

21919752 is a wasteful number, since it uses less digits than its factorization.

21919752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2002 (or 1995 counting only the distinct ones).

The product of its digits is 11340, while the sum is 36.

The square root of 21919752 is about 4681.8534791255. The cubic root of 21919752 is about 279.8628239629.

The spelling of 21919752 in words is "twenty-one million, nine hundred nineteen thousand, seven hundred fifty-two".