78957791 has 8 divisors (see below), whose sum is σ = 87969024. Its totient is φ = 70252120.

The previous prime is 78957773. The next prime is 78957793. The reversal of 78957791 is 19775987.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78957791 - 2⁶ = 78957727 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78957793) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75845 + ... + 76878.

It is an arithmetic number, because the mean of its divisors is an integer number (10996128).

Almost surely, 2^78957791 is an apocalyptic number.

78957791 is a deficient number, since it is larger than the sum of its proper divisors (9011233).

78957791 is a wasteful number, since it uses less digits than its factorization.

78957791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152781.

The product of its digits is 1111320, while the sum is 53.

The square root of 78957791 is about 8885.8196583095. The cubic root of 78957791 is about 429.0076104880.

The spelling of 78957791 in words is "seventy-eight million, nine hundred fifty-seven thousand, seven hundred ninety-one".