91143705637 has 2 divisors, whose sum is σ = 91143705638. Its totient is φ = 91143705636.

The previous prime is 91143705593. The next prime is 91143705643. The reversal of 91143705637 is 73650734119.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84731059396 + 6412646241 = 291086^2 + 80079^2 .

It is an emirp because it is prime and its reverse (73650734119) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91143705637 - 2²³ = 91135317029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91143705677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45571852818 + 45571852819.

It is an arithmetic number, because the mean of its divisors is an integer number (45571852819).

Almost surely, 2^91143705637 is an apocalyptic number.

It is an amenable number.

91143705637 is a deficient number, since it is larger than the sum of its proper divisors (1).

91143705637 is an equidigital number, since it uses as much as digits as its factorization.

91143705637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 476280, while the sum is 46.

The spelling of 91143705637 in words is "ninety-one billion, one hundred forty-three million, seven hundred five thousand, six hundred thirty-seven".