78157 has 2 divisors, whose sum is σ = 78158. Its totient is φ = 78156.

The previous prime is 78139. The next prime is 78163. The reversal of 78157 is 75187.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42436 + 35721 = 206^2 + 189^2 .

It is a cyclic number.

It is not a de Polignac number, because 78157 - 2¹⁵ = 45389 is a prime.

It is a super-2 number, since 2×78157² = 12217033298, which contains 22 as substring.

It is a Chen prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39078 + 39079.

It is an arithmetic number, because the mean of its divisors is an integer number (39079).

2⁷⁸¹⁵⁷ is an apocalyptic number.

It is an amenable number.

78157 is a deficient number, since it is larger than the sum of its proper divisors (1).

78157 is an equidigital number, since it uses as much as digits as its factorization.

78157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1960, while the sum is 28.

The square root of 78157 is about 279.5657346672. The cubic root of 78157 is about 42.7552345881.

It can be divided in two parts, 781 and 57, that added together give a palindrome (838).

The spelling of 78157 in words is "seventy-eight thousand, one hundred fifty-seven".