91299611881 has 2 divisors, whose sum is σ = 91299611882. Its totient is φ = 91299611880.

The previous prime is 91299611873. The next prime is 91299611933. The reversal of 91299611881 is 18811699219.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52230531600 + 39069080281 = 228540^2 + 197659^2 .

It is an emirp because it is prime and its reverse (18811699219) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91299611881 - 2³ = 91299611873 is a prime.

It is a super-2 number, since 2×91299611881² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91299611801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45649805940 + 45649805941.

It is an arithmetic number, because the mean of its divisors is an integer number (45649805941).

Almost surely, 2^91299611881 is an apocalyptic number.

It is an amenable number.

91299611881 is a deficient number, since it is larger than the sum of its proper divisors (1).

91299611881 is an equidigital number, since it uses as much as digits as its factorization.

91299611881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 559872, while the sum is 55.

The spelling of 91299611881 in words is "ninety-one billion, two hundred ninety-nine million, six hundred eleven thousand, eight hundred eighty-one".