91040840 has 32 divisors (see below), whose sum is σ = 223464960. Its totient is φ = 33105600.

The previous prime is 91040827. The next prime is 91040861. The reversal of 91040840 is 4804019.

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, 103016 + ... + 103895.

It is an arithmetic number, because the mean of its divisors is an integer number (6983280).

Almost surely, 2^91040840 is an apocalyptic number.

It is an amenable number.

91040840 is an abundant number, since it is smaller than the sum of its proper divisors (132424120).

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

91040840 is a wasteful number, since it uses less digits than its factorization.

91040840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206933 (or 206929 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 91040840 is about 9541.5323716896. The cubic root of 91040840 is about 449.8614223499.

Adding to 91040840 its reverse (4804019), we get a palindrome (95844859).

The spelling of 91040840 in words is "ninety-one million, forty thousand, eight hundred forty".