91031616 has 84 divisors (see below), whose sum is σ = 281020012. Its totient is φ = 28007424.

The previous prime is 91031579. The next prime is 91031623. The reversal of 91031616 is 61613019.

91031616 is a `hidden beast` number, since 9 + 10 + 31 + 616 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8294400 + 82737216 = 2880^2 + 9096^2 .

It is a super-2 number, since 2×91031616² = 16573510223142912, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91031616.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1410 + ... + 13566.

Almost surely, 2^91031616 is an apocalyptic number.

91031616 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91031616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140510006).

91031616 is an abundant number, since it is smaller than the sum of its proper divisors (189988396).

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

91031616 is a wasteful number, since it uses less digits than its factorization.

91031616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12188 (or 12175 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 91031616 is about 9541.0489989309. The cubic root of 91031616 is about 449.8462289418.

The spelling of 91031616 in words is "ninety-one million, thirty-one thousand, six hundred sixteen".