91004115513221 has 4 divisors (see below), whose sum is σ = 91004138827500. Its totient is φ = 91004092198944.

The previous prime is 91004115513193. The next prime is 91004115513251. The reversal of 91004115513221 is 12231551140019.

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 2978251029121 + 88025864484100 = 1725761^2 + 9382210^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91004115513221 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 (91004115513251) 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, 4220846 + ... + 14135903.

It is an arithmetic number, because the mean of its divisors is an integer number (22751034706875).

Almost surely, 2^{91004115513221} is an apocalyptic number.

It is an amenable number.

91004115513221 is a deficient number, since it is larger than the sum of its proper divisors (23314279).

91004115513221 is a wasteful number, since it uses less digits than its factorization.

91004115513221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23314278.

The product of its (nonzero) digits is 10800, while the sum is 35.

The spelling of 91004115513221 in words is "ninety-one trillion, four billion, one hundred fifteen million, five hundred thirteen thousand, two hundred twenty-one".