91478279 has 4 divisors (see below), whose sum is σ = 91586376. Its totient is φ = 91370184.

The previous prime is 91478269. The next prime is 91478281. The reversal of 91478279 is 97287419.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91478279 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 (91478269) 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, 52769 + ... + 54474.

It is an arithmetic number, because the mean of its divisors is an integer number (22896594).

Almost surely, 2^91478279 is an apocalyptic number.

91478279 is a deficient number, since it is larger than the sum of its proper divisors (108097).

91478279 is a wasteful number, since it uses less digits than its factorization.

91478279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108096.

The product of its digits is 254016, while the sum is 47.

The square root of 91478279 is about 9564.4277926074. The cubic root of 91478279 is about 450.5807793298.

The spelling of 91478279 in words is "ninety-one million, four hundred seventy-eight thousand, two hundred seventy-nine".