91409645990 has 32 divisors (see below), whose sum is σ = 177324620256. Its totient is φ = 33726389760.

The previous prime is 91409645969. The next prime is 91409646131. The reversal of 91409645990 is 9954690419.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81392 + ... + 435251.

It is an arithmetic number, because the mean of its divisors is an integer number (5541394383).

Almost surely, 2^91409645990 is an apocalyptic number.

91409645990 is a deficient number, since it is larger than the sum of its proper divisors (85914974266).

91409645990 is a wasteful number, since it uses less digits than its factorization.

91409645990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518024.

The product of its (nonzero) digits is 3149280, while the sum is 56.

The spelling of 91409645990 in words is "ninety-one billion, four hundred nine million, six hundred forty-five thousand, nine hundred ninety".