91287035280 has 480 divisors, whose sum is σ = 358838937600. Its totient is φ = 20788669440.

The previous prime is 91287035239. The next prime is 91287035291. The reversal of 91287035280 is 8253078219.

It is a happy number.

91287035280 is a `hidden beast` number, since 91 + 287 + 0 + 3 + 5 + 280 = 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, 92115585 + ... + 92116575.

It is an arithmetic number, because the mean of its divisors is an integer number (747581120).

Almost surely, 2^91287035280 is an apocalyptic number.

91287035280 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 91287035280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179419468800).

91287035280 is an abundant number, since it is smaller than the sum of its proper divisors (267551902320).

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

91287035280 is a wasteful number, since it uses less digits than its factorization.

91287035280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1404 (or 1381 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 91287035280 in words is "ninety-one billion, two hundred eighty-seven million, thirty-five thousand, two hundred eighty".