91550420281 has 2 divisors, whose sum is σ = 91550420282. Its totient is φ = 91550420280.

The previous prime is 91550420279. The next prime is 91550420341. The reversal of 91550420281 is 18202405519.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 83468410281 + 8082010000 = 288909^2 + 89900^2 .

It is a cyclic number.

It is not a de Polignac number, because 91550420281 - 2¹ = 91550420279 is a prime.

It is a super-2 number, since 2×91550420281² (a number of 23 digits) contains 22 as substring.

Together with 91550420279, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 91550420281.

It is not a weakly prime, because it can be changed into another prime (91550420201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45775210140 + 45775210141.

It is an arithmetic number, because the mean of its divisors is an integer number (45775210141).

Almost surely, 2^91550420281 is an apocalyptic number.

It is an amenable number.

91550420281 is a deficient number, since it is larger than the sum of its proper divisors (1).

91550420281 is an equidigital number, since it uses as much as digits as its factorization.

91550420281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28800, while the sum is 37.

The spelling of 91550420281 in words is "ninety-one billion, five hundred fifty million, four hundred twenty thousand, two hundred eighty-one".