91370172768 has 384 divisors, whose sum is σ = 289302773760. Its totient is φ = 24704040960.

The previous prime is 91370172767. The next prime is 91370172781. The reversal of 91370172768 is 86727107319.

It is a self number, because there is not a number n which added to its sum of digits gives 91370172768.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91370172767) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 208132293 + ... + 208132731.

It is an arithmetic number, because the mean of its divisors is an integer number (753392640).

Almost surely, 2^91370172768 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91370172768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144651386880).

91370172768 is an abundant number, since it is smaller than the sum of its proper divisors (197932600992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91370172768 is a wasteful number, since it uses less digits than its factorization.

91370172768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690 (or 682 counting only the distinct ones).

The product of its (nonzero) digits is 889056, while the sum is 51.

The spelling of 91370172768 in words is "ninety-one billion, three hundred seventy million, one hundred seventy-two thousand, seven hundred sixty-eight".