91993878306 has 192 divisors, whose sum is σ = 228605932800. Its totient is φ = 27397370880.

The previous prime is 91993878283. The next prime is 91993878307. The reversal of 91993878306 is 60387839919.

91993878306 is a `hidden beast` number, since 91 + 99 + 387 + 83 + 0 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (91993878307) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 109646635 + ... + 109647473.

It is an arithmetic number, because the mean of its divisors is an integer number (1190655900).

Almost surely, 2^91993878306 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91993878306, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114302966400).

91993878306 is an abundant number, since it is smaller than the sum of its proper divisors (136612054494).

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

91993878306 is a wasteful number, since it uses less digits than its factorization.

91993878306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1142 (or 1125 counting only the distinct ones).

The product of its (nonzero) digits is 17635968, while the sum is 63.

It can be divided in two parts, 91993 and 878306, that added together give a cube (970299 = 99³).

The spelling of 91993878306 in words is "ninety-one billion, nine hundred ninety-three million, eight hundred seventy-eight thousand, three hundred six".