78342157 has 2 divisors, whose sum is σ = 78342158. Its totient is φ = 78342156.

The previous prime is 78342127. The next prime is 78342169. The reversal of 78342157 is 75124387.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39765636 + 38576521 = 6306^2 + 6211^2 .

It is a cyclic number.

It is not a de Polignac number, because 78342157 - 2²³ = 69953549 is a prime.

It is a super-2 number, since 2×78342157² = 12274987126825298, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78342127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39171078 + 39171079.

It is an arithmetic number, because the mean of its divisors is an integer number (39171079).

Almost surely, 2^78342157 is an apocalyptic number.

It is an amenable number.

78342157 is a deficient number, since it is larger than the sum of its proper divisors (1).

78342157 is an equidigital number, since it uses as much as digits as its factorization.

78342157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47040, while the sum is 37.

The square root of 78342157 is about 8851.1104952994. The cubic root of 78342157 is about 427.8897090405.

The spelling of 78342157 in words is "seventy-eight million, three hundred forty-two thousand, one hundred fifty-seven".