91881504 has 288 divisors, whose sum is σ = 323616384. Its totient is φ = 24330240.

The previous prime is 91881487. The next prime is 91881521. The reversal of 91881504 is 40518819.

It is an interprime number because it is at equal distance from previous prime (91881487) and next prime (91881521).

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

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 947184 + ... + 947280.

It is an arithmetic number, because the mean of its divisors is an integer number (1123668).

Almost surely, 2^91881504 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 91881504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (161808192).

91881504 is an abundant number, since it is smaller than the sum of its proper divisors (231734880).

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

91881504 is a wasteful number, since it uses less digits than its factorization.

91881504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 91881504 is about 9585.4840253375. The cubic root of 91881504 is about 451.2418438634.

The spelling of 91881504 in words is "ninety-one million, eight hundred eighty-one thousand, five hundred four".