91971961135 has 8 divisors (see below), whose sum is σ = 110368172016. Its totient is φ = 73576356480.

The previous prime is 91971961129. The next prime is 91971961157. The reversal of 91971961135 is 53116917919.

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

It is not a de Polignac number, because 91971961135 - 2³¹ = 89824477487 is a prime.

It is a super-3 number, since 3×91971961135³ (a number of 34 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 310012 + ... + 529198.

It is an arithmetic number, because the mean of its divisors is an integer number (13796021502).

Almost surely, 2^91971961135 is an apocalyptic number.

91971961135 is a deficient number, since it is larger than the sum of its proper divisors (18396210881).

91971961135 is a wasteful number, since it uses less digits than its factorization.

91971961135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303113.

The product of its digits is 459270, while the sum is 52.

The spelling of 91971961135 in words is "ninety-one billion, nine hundred seventy-one million, nine hundred sixty-one thousand, one hundred thirty-five".