123157 has 4 divisors (see below), whose sum is σ = 124416. Its totient is φ = 121900.

The previous prime is 123143. The next prime is 123169. The reversal of 123157 is 751321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123157 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 (123127) 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, 469 + ... + 682.

It is an arithmetic number, because the mean of its divisors is an integer number (31104).

2¹²³¹⁵⁷ is an apocalyptic number.

It is an amenable number.

123157 is a deficient number, since it is larger than the sum of its proper divisors (1259).

123157 is a wasteful number, since it uses less digits than its factorization.

123157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1258.

The product of its digits is 210, while the sum is 19.

The square root of 123157 is about 350.9373163401. The cubic root of 123157 is about 49.7530489786.

Adding to 123157 its reverse (751321), we get a palindrome (874478).

The spelling of 123157 in words is "one hundred twenty-three thousand, one hundred fifty-seven".