123139837 has 4 divisors (see below), whose sum is σ = 123164860. Its totient is φ = 123114816.

The previous prime is 123139813. The next prime is 123139853. The reversal of 123139837 is 738931321.

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 122014116 + 1125721 = 11046^2 + 1061^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123139837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 123139796 and 123139805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123139897) 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, 2412 + ... + 15877.

It is an arithmetic number, because the mean of its divisors is an integer number (30791215).

Almost surely, 2^123139837 is an apocalyptic number.

It is an amenable number.

123139837 is a deficient number, since it is larger than the sum of its proper divisors (25023).

123139837 is an equidigital number, since it uses as much as digits as its factorization.

123139837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25022.

The product of its digits is 27216, while the sum is 37.

The square root of 123139837 is about 11096.8390544335. The cubic root of 123139837 is about 497.5073769771.

The spelling of 123139837 in words is "one hundred twenty-three million, one hundred thirty-nine thousand, eight hundred thirty-seven".