20943972 has 108 divisors (see below), whose sum is σ = 63737856. Its totient is φ = 5775840.

The previous prime is 20943953. The next prime is 20943973. The reversal of 20943972 is 27934902.

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 (20943973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 54493 + ... + 54875.

Almost surely, 2^20943972 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 20943972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31868928).

20943972 is an abundant number, since it is smaller than the sum of its proper divisors (42793884).

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

20943972 is a wasteful number, since it uses less digits than its factorization.

20943972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438 (or 426 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 20943972 is about 4576.4584560553. The cubic root of 20943972 is about 275.6468387836.

The spelling of 20943972 in words is "twenty million, nine hundred forty-three thousand, nine hundred seventy-two".