191662520837 has 2 divisors, whose sum is σ = 191662520838. Its totient is φ = 191662520836.

The previous prime is 191662520761. The next prime is 191662520857. The reversal of 191662520837 is 738025266191.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139656174436 + 52006346401 = 373706^2 + 228049^2 .

It is a cyclic number.

It is not a de Polignac number, because 191662520837 - 2¹² = 191662516741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191662520857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95831260418 + 95831260419.

It is an arithmetic number, because the mean of its divisors is an integer number (95831260419).

Almost surely, 2^191662520837 is an apocalyptic number.

It is an amenable number.

191662520837 is a deficient number, since it is larger than the sum of its proper divisors (1).

191662520837 is an equidigital number, since it uses as much as digits as its factorization.

191662520837 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088640, while the sum is 50.

The spelling of 191662520837 in words is "one hundred ninety-one billion, six hundred sixty-two million, five hundred twenty thousand, eight hundred thirty-seven".