20139387511 has 4 divisors (see below), whose sum is σ = 20166205024. Its totient is φ = 20112570000.

The previous prime is 20139387487. The next prime is 20139387559. The reversal of 20139387511 is 11578393102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20139387511 - 2¹⁵ = 20139354743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20139397511) 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, 13407630 + ... + 13409131.

It is an arithmetic number, because the mean of its divisors is an integer number (5041551256).

Almost surely, 2^20139387511 is an apocalyptic number.

20139387511 is a deficient number, since it is larger than the sum of its proper divisors (26817513).

20139387511 is an equidigital number, since it uses as much as digits as its factorization.

20139387511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26817512.

The product of its (nonzero) digits is 45360, while the sum is 40.

The spelling of 20139387511 in words is "twenty billion, one hundred thirty-nine million, three hundred eighty-seven thousand, five hundred eleven".