78961157 has 4 divisors (see below), whose sum is σ = 86139456. Its totient is φ = 71782860.

The previous prime is 78961153. The next prime is 78961163. The reversal of 78961157 is 75116987.

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 not a de Polignac number, because 78961157 - 2² = 78961153 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 (78961153) 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, 3589133 + ... + 3589154.

It is an arithmetic number, because the mean of its divisors is an integer number (21534864).

Almost surely, 2^78961157 is an apocalyptic number.

It is an amenable number.

78961157 is a deficient number, since it is larger than the sum of its proper divisors (7178299).

78961157 is a wasteful number, since it uses less digits than its factorization.

78961157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7178298.

The product of its digits is 105840, while the sum is 44.

The square root of 78961157 is about 8886.0090591896. The cubic root of 78961157 is about 429.0137066527.

The spelling of 78961157 in words is "seventy-eight million, nine hundred sixty-one thousand, one hundred fifty-seven".