91903760640 has 864 divisors, whose sum is σ = 349699424256. Its totient is φ = 22213509120.

The previous prime is 91903760591. The next prime is 91903760701. The reversal of 91903760640 is 4606730919.

91903760640 is a `hidden beast` number, since 9 + 1 + 9 + 0 + 37 + 606 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 550321837 + ... + 550322003.

It is an arithmetic number, because the mean of its divisors is an integer number (404744704).

Almost surely, 2^91903760640 is an apocalyptic number.

91903760640 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91903760640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (174849712128).

91903760640 is an abundant number, since it is smaller than the sum of its proper divisors (257795663616).

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

91903760640 is a wasteful number, since it uses less digits than its factorization.

91903760640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315 (or 298 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The spelling of 91903760640 in words is "ninety-one billion, nine hundred three million, seven hundred sixty thousand, six hundred forty".