20138115507 has 4 divisors (see below), whose sum is σ = 26850820680. Its totient is φ = 13425410336.

The previous prime is 20138115457. The next prime is 20138115511. The reversal of 20138115507 is 70551183102.

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 20138115507 - 2¹⁰ = 20138114483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20138115007) 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, 3356352582 + ... + 3356352587.

It is an arithmetic number, because the mean of its divisors is an integer number (6712705170).

Almost surely, 2^20138115507 is an apocalyptic number.

20138115507 is a deficient number, since it is larger than the sum of its proper divisors (6712705173).

20138115507 is an equidigital number, since it uses as much as digits as its factorization.

20138115507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6712705172.

The product of its (nonzero) digits is 8400, while the sum is 33.

Adding to 20138115507 its reverse (70551183102), we get a palindrome (90689298609).

The spelling of 20138115507 in words is "twenty billion, one hundred thirty-eight million, one hundred fifteen thousand, five hundred seven".