20139515 has 8 divisors (see below), whose sum is σ = 26364528. Its totient is φ = 14646880.

The previous prime is 20139503. The next prime is 20139517. The reversal of 20139515 is 51593102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20139515 - 2⁴ = 20139499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20139517) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 183032 + ... + 183141.

It is an arithmetic number, because the mean of its divisors is an integer number (3295566).

Almost surely, 2^20139515 is an apocalyptic number.

20139515 is a deficient number, since it is larger than the sum of its proper divisors (6225013).

20139515 is a wasteful number, since it uses less digits than its factorization.

20139515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366189.

The product of its (nonzero) digits is 1350, while the sum is 26.

The square root of 20139515 is about 4487.7070982853. The cubic root of 20139515 is about 272.0714696492.

The spelling of 20139515 in words is "twenty million, one hundred thirty-nine thousand, five hundred fifteen".