78712991 has 8 divisors (see below), whose sum is σ = 94692480. Its totient is φ = 63917208.

The previous prime is 78712987. The next prime is 78713027. The reversal of 78712991 is 19921787.

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 78712991 - 2² = 78712987 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 (78712901) 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, 295781 + ... + 296046.

It is an arithmetic number, because the mean of its divisors is an integer number (11836560).

Almost surely, 2^78712991 is an apocalyptic number.

78712991 is a deficient number, since it is larger than the sum of its proper divisors (15979489).

78712991 is a wasteful number, since it uses less digits than its factorization.

78712991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 591853.

The product of its digits is 63504, while the sum is 44.

The square root of 78712991 is about 8872.0342086807. The cubic root of 78712991 is about 428.5637877632.

The spelling of 78712991 in words is "seventy-eight million, seven hundred twelve thousand, nine hundred ninety-one".