91304838557 has 2 divisors, whose sum is σ = 91304838558. Its totient is φ = 91304838556.

The previous prime is 91304838553. The next prime is 91304838571. The reversal of 91304838557 is 75583840319.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90351943396 + 952895161 = 300586^2 + 30869^2 .

It is a cyclic number.

It is not a de Polignac number, because 91304838557 - 2² = 91304838553 is a prime.

It is a super-3 number, since 3×91304838557³ (a number of 34 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 91304838499 and 91304838508.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91304838553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45652419278 + 45652419279.

It is an arithmetic number, because the mean of its divisors is an integer number (45652419279).

Almost surely, 2^91304838557 is an apocalyptic number.

It is an amenable number.

91304838557 is a deficient number, since it is larger than the sum of its proper divisors (1).

91304838557 is an equidigital number, since it uses as much as digits as its factorization.

91304838557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3628800, while the sum is 53.

The spelling of 91304838557 in words is "ninety-one billion, three hundred four million, eight hundred thirty-eight thousand, five hundred fifty-seven".