91678739 has 8 divisors (see below), whose sum is σ = 97203888. Its totient is φ = 86168320.

The previous prime is 91678733. The next prime is 91678771. The reversal of 91678739 is 93787619.

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 91678739 - 2⁴ = 91678723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91678733) 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, 10799 + ... + 17319.

It is an arithmetic number, because the mean of its divisors is an integer number (12150486).

Almost surely, 2^91678739 is an apocalyptic number.

91678739 is a deficient number, since it is larger than the sum of its proper divisors (5525149).

91678739 is a wasteful number, since it uses less digits than its factorization.

91678739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7365.

The product of its digits is 571536, while the sum is 50.

The square root of 91678739 is about 9574.9015138538. The cubic root of 91678739 is about 450.9096644224.

The spelling of 91678739 in words is "ninety-one million, six hundred seventy-eight thousand, seven hundred thirty-nine".