91971958695 has 64 divisors (see below), whose sum is σ = 158803476480. Its totient is φ = 45306649728.

The previous prime is 91971958693. The next prime is 91971958703. The reversal of 91971958695 is 59685917919.

It is not a de Polignac number, because 91971958695 - 2¹ = 91971958693 is a prime.

It is a super-3 number, since 3×91971958695³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91971958693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3509832 + ... + 3535938.

It is an arithmetic number, because the mean of its divisors is an integer number (2481304320).

Almost surely, 2^91971958695 is an apocalyptic number.

91971958695 is a gapful number since it is divisible by the number (95) formed by its first and last digit.

91971958695 is a deficient number, since it is larger than the sum of its proper divisors (66831517785).

91971958695 is a wasteful number, since it uses less digits than its factorization.

91971958695 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26444.

The product of its digits is 55112400, while the sum is 69.

The spelling of 91971958695 in words is "ninety-one billion, nine hundred seventy-one million, nine hundred fifty-eight thousand, six hundred ninety-five".