91211771253 has 32 divisors (see below), whose sum is σ = 129823119360. Its totient is φ = 56763150080.

The previous prime is 91211771251. The next prime is 91211771263. The reversal of 91211771253 is 35217711219.

It is a cyclic number.

It is not a de Polignac number, because 91211771253 - 2¹ = 91211771251 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91211771251) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22359268 + ... + 22363346.

It is an arithmetic number, because the mean of its divisors is an integer number (4056972480).

Almost surely, 2^91211771253 is an apocalyptic number.

It is an amenable number.

91211771253 is a deficient number, since it is larger than the sum of its proper divisors (38611348107).

91211771253 is a wasteful number, since it uses less digits than its factorization.

91211771253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7577.

The product of its digits is 26460, while the sum is 39.

The spelling of 91211771253 in words is "ninety-one billion, two hundred eleven million, seven hundred seventy-one thousand, two hundred fifty-three".