91129440 has 48 divisors (see below), whose sum is σ = 287059248. Its totient is φ = 24301056.

The previous prime is 91129433. The next prime is 91129457. The reversal of 91129440 is 4492119.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 91129398 and 91129407.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94447 + ... + 95406.

It is an arithmetic number, because the mean of its divisors is an integer number (5980401).

Almost surely, 2^91129440 is an apocalyptic number.

It is an amenable number.

91129440 is an abundant number, since it is smaller than the sum of its proper divisors (195929808).

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

91129440 is a wasteful number, since it uses less digits than its factorization.

91129440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189871 (or 189863 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 91129440 is about 9546.1741027492. The cubic root of 91129440 is about 450.0073085233.

The spelling of 91129440 in words is "ninety-one million, one hundred twenty-nine thousand, four hundred forty".