139121813 has 8 divisors (see below), whose sum is σ = 146206368. Its totient is φ = 132212304.

The previous prime is 139121809. The next prime is 139121821. The reversal of 139121813 is 318121931.

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

It is a cyclic number.

It is not a de Polignac number, because 139121813 - 2² = 139121809 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 (139121803) 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, 42131 + ... + 45312.

It is an arithmetic number, because the mean of its divisors is an integer number (18275796).

Almost surely, 2^139121813 is an apocalyptic number.

It is an amenable number.

139121813 is a deficient number, since it is larger than the sum of its proper divisors (7084555).

139121813 is an equidigital number, since it uses as much as digits as its factorization.

139121813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87523.

The product of its digits is 1296, while the sum is 29.

The square root of 139121813 is about 11794.9910131377. The cubic root of 139121813 is about 518.1614223885.

The spelling of 139121813 in words is "one hundred thirty-nine million, one hundred twenty-one thousand, eight hundred thirteen".