91878309697 has 8 divisors (see below), whose sum is σ = 92235877632. Its totient is φ = 91521435600.

The previous prime is 91878309661. The next prime is 91878309713. The reversal of 91878309697 is 79690387819.

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 91878309697 - 2²³ = 91869921089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91878309197) 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, 92688 + ... + 438574.

It is an arithmetic number, because the mean of its divisors is an integer number (11529484704).

Almost surely, 2^91878309697 is an apocalyptic number.

It is an amenable number.

91878309697 is a deficient number, since it is larger than the sum of its proper divisors (357567935).

91878309697 is a wasteful number, since it uses less digits than its factorization.

91878309697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346919.

The product of its (nonzero) digits is 41150592, while the sum is 67.

The spelling of 91878309697 in words is "ninety-one billion, eight hundred seventy-eight million, three hundred nine thousand, six hundred ninety-seven".