20888740 has 12 divisors (see below), whose sum is σ = 43866396. Its totient is φ = 8355488.

The previous prime is 20888723. The next prime is 20888741. The reversal of 20888740 is 4788802.

It can be written as a sum of positive squares in 2 ways, for example, as 12902464 + 7986276 = 3592^2 + 2826^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20888740.

It is not an unprimeable number, because it can be changed into a prime (20888741) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 522199 + ... + 522238.

It is an arithmetic number, because the mean of its divisors is an integer number (3655533).

Almost surely, 2^20888740 is an apocalyptic number.

20888740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20888740 is an abundant number, since it is smaller than the sum of its proper divisors (22977656).

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

20888740 is a wasteful number, since it uses less digits than its factorization.

20888740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044446 (or 1044444 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 37.

The square root of 20888740 is about 4570.4201119810. The cubic root of 20888740 is about 275.4043198563.

The spelling of 20888740 in words is "twenty million, eight hundred eighty-eight thousand, seven hundred forty".