20375720 has 16 divisors (see below), whose sum is σ = 45845460. Its totient is φ = 8150272.

The previous prime is 20375699. The next prime is 20375743. The reversal of 20375720 is 2757302.

It can be written as a sum of positive squares in 2 ways, for example, as 18852964 + 1522756 = 4342^2 + 1234^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20375720.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 254657 + ... + 254736.

Almost surely, 2^20375720 is an apocalyptic number.

20375720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20375720 is an abundant number, since it is smaller than the sum of its proper divisors (25469740).

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

20375720 is a wasteful number, since it uses less digits than its factorization.

20375720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 509404 (or 509400 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 26.

The square root of 20375720 is about 4513.9472748361. The cubic root of 20375720 is about 273.1309957368.

The spelling of 20375720 in words is "twenty million, three hundred seventy-five thousand, seven hundred twenty".