91441257155557 has 2 divisors, whose sum is σ = 91441257155558. Its totient is φ = 91441257155556.

The previous prime is 91441257155533. The next prime is 91441257155561. The reversal of 91441257155557 is 75555175214419.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65973479228836 + 25467777926721 = 8122406^2 + 5046561^2 .

It is a cyclic number.

It is not a de Polignac number, because 91441257155557 - 2¹¹ = 91441257153509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91441257155495 and 91441257155504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91441257155657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45720628577778 + 45720628577779.

It is an arithmetic number, because the mean of its divisors is an integer number (45720628577779).

Almost surely, 2^{91441257155557} is an apocalyptic number.

It is an amenable number.

91441257155557 is a deficient number, since it is larger than the sum of its proper divisors (1).

91441257155557 is an equidigital number, since it uses as much as digits as its factorization.

91441257155557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 44100000, while the sum is 61.

The spelling of 91441257155557 in words is "ninety-one trillion, four hundred forty-one billion, two hundred fifty-seven million, one hundred fifty-five thousand, five hundred fifty-seven".