91321253 has 4 divisors (see below), whose sum is σ = 91369068. Its totient is φ = 91273440.

The previous prime is 91321249. The next prime is 91321259. The reversal of 91321253 is 35212319.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 83576164 + 7745089 = 9142^2 + 2783^2 .

It is a cyclic number.

It is not a de Polignac number, because 91321253 - 2² = 91321249 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91321259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20918 + ... + 24903.

It is an arithmetic number, because the mean of its divisors is an integer number (22842267).

Almost surely, 2^91321253 is an apocalyptic number.

It is an amenable number.

91321253 is a deficient number, since it is larger than the sum of its proper divisors (47815).

91321253 is a wasteful number, since it uses less digits than its factorization.

91321253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47814.

The product of its digits is 1620, while the sum is 26.

The square root of 91321253 is about 9556.2154119714. The cubic root of 91321253 is about 450.3228185685.

The spelling of 91321253 in words is "ninety-one million, three hundred twenty-one thousand, two hundred fifty-three".