15971138551 has 2 divisors, whose sum is σ = 15971138552. Its totient is φ = 15971138550.

The previous prime is 15971138549. The next prime is 15971138591. The reversal of 15971138551 is 15583117951.

It is a weak prime.

It is an emirp because it is prime and its reverse (15583117951) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15971138551 - 2¹ = 15971138549 is a prime.

Together with 15971138549, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15971138591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7985569275 + 7985569276.

It is an arithmetic number, because the mean of its divisors is an integer number (7985569276).

Almost surely, 2^15971138551 is an apocalyptic number.

15971138551 is a deficient number, since it is larger than the sum of its proper divisors (1).

15971138551 is an equidigital number, since it uses as much as digits as its factorization.

15971138551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 189000, while the sum is 46.

The spelling of 15971138551 in words is "fifteen billion, nine hundred seventy-one million, one hundred thirty-eight thousand, five hundred fifty-one".