15591573197 has 2 divisors, whose sum is σ = 15591573198. Its totient is φ = 15591573196.

The previous prime is 15591573187. The next prime is 15591573199. The reversal of 15591573197 is 79137519551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13150126276 + 2441446921 = 114674^2 + 49411^2 .

It is a cyclic number.

It is not a de Polignac number, because 15591573197 - 2⁶ = 15591573133 is a prime.

Together with 15591573199, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15591573199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7795786598 + 7795786599.

It is an arithmetic number, because the mean of its divisors is an integer number (7795786599).

Almost surely, 2^15591573197 is an apocalyptic number.

It is an amenable number.

15591573197 is a deficient number, since it is larger than the sum of its proper divisors (1).

15591573197 is an equidigital number, since it uses as much as digits as its factorization.

15591573197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1488375, while the sum is 53.

The spelling of 15591573197 in words is "fifteen billion, five hundred ninety-one million, five hundred seventy-three thousand, one hundred ninety-seven".