91412640 has 288 divisors, whose sum is σ = 353808000. Its totient is φ = 21288960.

The previous prime is 91412623. The next prime is 91412641. The reversal of 91412640 is 4621419.

91412640 is a `hidden beast` number, since 9 + 1 + 4 + 12 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is not an unprimeable number, because it can be changed into a prime (91412641) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 459261 + ... + 459459.

It is an arithmetic number, because the mean of its divisors is an integer number (1228500).

Almost surely, 2^91412640 is an apocalyptic number.

91412640 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 91412640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (176904000).

91412640 is an abundant number, since it is smaller than the sum of its proper divisors (262395360).

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

91412640 is a wasteful number, since it uses less digits than its factorization.

91412640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260 (or 249 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 91412640 is about 9560.9957640405. The cubic root of 91412640 is about 450.4729841650.

It can be divided in two parts, 9141 and 2640, that added together give a triangular number (11781 = T₁₅₃).

The spelling of 91412640 in words is "ninety-one million, four hundred twelve thousand, six hundred forty".