20258720 has 48 divisors (see below), whose sum is σ = 48784680. Its totient is φ = 7947264.

The previous prime is 20258663. The next prime is 20258737. The reversal of 20258720 is 2785202.

It can be written as a sum of positive squares in 4 ways, for example, as 15713296 + 4545424 = 3964^2 + 2132^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20258720.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7286 + ... + 9674.

Almost surely, 2^20258720 is an apocalyptic number.

20258720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20258720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24392340).

20258720 is an abundant number, since it is smaller than the sum of its proper divisors (28525960).

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

20258720 is a wasteful number, since it uses less digits than its factorization.

20258720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2457 (or 2449 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 20258720 is about 4500.9687846063. The cubic root of 20258720 is about 272.6072074870.

The spelling of 20258720 in words is "twenty million, two hundred fifty-eight thousand, seven hundred twenty".