15637873661 has 2 divisors, whose sum is σ = 15637873662. Its totient is φ = 15637873660.

The previous prime is 15637873583. The next prime is 15637873663. The reversal of 15637873661 is 16637873651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15250768036 + 387105625 = 123494^2 + 19675^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15637873661 is a prime.

Together with 15637873663, 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 (15637873663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7818936830 + 7818936831.

It is an arithmetic number, because the mean of its divisors is an integer number (7818936831).

Almost surely, 2^15637873661 is an apocalyptic number.

It is an amenable number.

15637873661 is a deficient number, since it is larger than the sum of its proper divisors (1).

15637873661 is an equidigital number, since it uses as much as digits as its factorization.

15637873661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3810240, while the sum is 53.

The spelling of 15637873661 in words is "fifteen billion, six hundred thirty-seven million, eight hundred seventy-three thousand, six hundred sixty-one".