91477731 has 16 divisors (see below), whose sum is σ = 129835008. Its totient is φ = 57091200.

The previous prime is 91477721. The next prime is 91477753. The reversal of 91477731 is 13777419.

It is not a de Polignac number, because 91477731 - 2¹⁴ = 91461347 is a prime.

It is a super-2 number, since 2×91477731² = 16736350537816722, 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 91477731.

It is not an unprimeable number, because it can be changed into a prime (91477721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5046 + ... + 14436.

It is an arithmetic number, because the mean of its divisors is an integer number (8114688).

Almost surely, 2^91477731 is an apocalyptic number.

91477731 is a deficient number, since it is larger than the sum of its proper divisors (38357277).

91477731 is a wasteful number, since it uses less digits than its factorization.

91477731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9602.

The product of its digits is 37044, while the sum is 39.

The square root of 91477731 is about 9564.3991447451. The cubic root of 91477731 is about 450.5798795943.

The spelling of 91477731 in words is "ninety-one million, four hundred seventy-seven thousand, seven hundred thirty-one".