91009431 has 6 divisors (see below), whose sum is σ = 131458080. Its totient is φ = 60672948.

The previous prime is 91009403. The next prime is 91009481. The reversal of 91009431 is 13490019.

It is not a de Polignac number, because 91009431 - 2²³ = 82620823 is a prime.

It is a super-2 number, since 2×91009431² = 16565433061887522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 91009395 and 91009404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91009481) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5056071 + ... + 5056088.

It is an arithmetic number, because the mean of its divisors is an integer number (21909680).

Almost surely, 2^91009431 is an apocalyptic number.

91009431 is a deficient number, since it is larger than the sum of its proper divisors (40448649).

91009431 is a wasteful number, since it uses less digits than its factorization.

91009431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10112165 (or 10112162 counting only the distinct ones).

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

The square root of 91009431 is about 9539.8863200774. The cubic root of 91009431 is about 449.8096824837.

The spelling of 91009431 in words is "ninety-one million, nine thousand, four hundred thirty-one".