20139193 has 4 divisors (see below), whose sum is σ = 20152548. Its totient is φ = 20125840.

The previous prime is 20139157. The next prime is 20139227. The reversal of 20139193 is 39193102.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4678569 + 15460624 = 2163^2 + 3932^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20139193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20139143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4078 + ... + 7543.

It is an arithmetic number, because the mean of its divisors is an integer number (5038137).

Almost surely, 2^20139193 is an apocalyptic number.

It is an amenable number.

20139193 is a deficient number, since it is larger than the sum of its proper divisors (13355).

20139193 is a wasteful number, since it uses less digits than its factorization.

20139193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13354.

The product of its (nonzero) digits is 1458, while the sum is 28.

The square root of 20139193 is about 4487.6712223602. The cubic root of 20139193 is about 272.0700196394.

The spelling of 20139193 in words is "twenty million, one hundred thirty-nine thousand, one hundred ninety-three".