15972172871 has 2 divisors, whose sum is σ = 15972172872. Its totient is φ = 15972172870.

The previous prime is 15972172819. The next prime is 15972172889. The reversal of 15972172871 is 17827127951.

It is a strong prime.

It is an emirp because it is prime and its reverse (17827127951) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15972172871 - 2⁶ = 15972172807 is a prime.

It is a super-2 number, since 2×15972172871² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15972172171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7986086435 + 7986086436.

It is an arithmetic number, because the mean of its divisors is an integer number (7986086436).

Almost surely, 2^15972172871 is an apocalyptic number.

15972172871 is a deficient number, since it is larger than the sum of its proper divisors (1).

15972172871 is an equidigital number, since it uses as much as digits as its factorization.

15972172871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 493920, while the sum is 50.

The spelling of 15972172871 in words is "fifteen billion, nine hundred seventy-two million, one hundred seventy-two thousand, eight hundred seventy-one".