91371431 has 16 divisors (see below), whose sum is σ = 98841600. Its totient is φ = 84281568.

The previous prime is 91371409. The next prime is 91371439. The reversal of 91371431 is 13417319.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 91371431 - 2¹⁰ = 91370407 is a prime.

It is a super-2 number, since 2×91371431² = 16697476805975522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91371394 and 91371403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91371439) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57830 + ... + 59388.

It is an arithmetic number, because the mean of its divisors is an integer number (6177600).

Almost surely, 2^91371431 is an apocalyptic number.

91371431 is a deficient number, since it is larger than the sum of its proper divisors (7470169).

91371431 is a wasteful number, since it uses less digits than its factorization.

91371431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1678.

The product of its digits is 2268, while the sum is 29.

The square root of 91371431 is about 9558.8404631524. The cubic root of 91371431 is about 450.4052826182.

The spelling of 91371431 in words is "ninety-one million, three hundred seventy-one thousand, four hundred thirty-one".