91631040 has 112 divisors (see below), whose sum is σ = 300410880. Its totient is φ = 23639040.

The previous prime is 91631021. The next prime is 91631051. The reversal of 91631040 is 4013619.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 91631040.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28221 + ... + 31299.

It is an arithmetic number, because the mean of its divisors is an integer number (2682240).

Almost surely, 2^91631040 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 91631040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (150205440).

91631040 is an abundant number, since it is smaller than the sum of its proper divisors (208779840).

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

91631040 is a wasteful number, since it uses less digits than its factorization.

91631040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3130 (or 3120 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 91631040 is about 9572.4103547644. The cubic root of 91631040 is about 450.8314504640.

Adding to 91631040 its reverse (4013619), we get a palindrome (95644659).

The spelling of 91631040 in words is "ninety-one million, six hundred thirty-one thousand, forty".