20509038 has 80 divisors (see below), whose sum is σ = 53160624. Its totient is φ = 5840640.

The previous prime is 20508997. The next prime is 20509057. The reversal of 20509038 is 83090502.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 29956 + ... + 30632.

Almost surely, 2^20509038 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20509038, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26580312).

20509038 is an abundant number, since it is smaller than the sum of its proper divisors (32651586).

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

20509038 is a wasteful number, since it uses less digits than its factorization.

20509038 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 719 (or 710 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 20509038 is about 4528.6905392177. The cubic root of 20509038 is about 273.7253984272.

The spelling of 20509038 in words is "twenty million, five hundred nine thousand, thirty-eight".