91751768501 has 4 divisors (see below), whose sum is σ = 97148931372. Its totient is φ = 86354605632.

The previous prime is 91751768473. The next prime is 91751768503. The reversal of 91751768501 is 10586715719.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10586715719 = 73 ⋅145023503.

It can be written as a sum of positive squares in 2 ways, for example, as 71288466001 + 20463302500 = 266999^2 + 143050^2 .

It is a cyclic number.

It is not a de Polignac number, because 91751768501 - 2³⁴ = 74571899317 is a prime.

It is a super-2 number, since 2×91751768501² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91751768501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91751768503) 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, 2698581410 + ... + 2698581443.

It is an arithmetic number, because the mean of its divisors is an integer number (24287232843).

Almost surely, 2^91751768501 is an apocalyptic number.

It is an amenable number.

91751768501 is a deficient number, since it is larger than the sum of its proper divisors (5397162871).

91751768501 is a wasteful number, since it uses less digits than its factorization.

91751768501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5397162870.

The product of its (nonzero) digits is 529200, while the sum is 50.

The spelling of 91751768501 in words is "ninety-one billion, seven hundred fifty-one million, seven hundred sixty-eight thousand, five hundred one".