17215939978031 has 2 divisors, whose sum is σ = 17215939978032. Its totient is φ = 17215939978030.

The previous prime is 17215939977983. The next prime is 17215939978037. The reversal of 17215939978031 is 13087993951271.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17215939978031 is a prime.

It is a super-2 number, since 2×17215939978031² (a number of 27 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17215939978037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8607969989015 + 8607969989016.

It is an arithmetic number, because the mean of its divisors is an integer number (8607969989016).

Almost surely, 2^{17215939978031} is an apocalyptic number.

17215939978031 is a deficient number, since it is larger than the sum of its proper divisors (1).

17215939978031 is an equidigital number, since it uses as much as digits as its factorization.

17215939978031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25719120, while the sum is 65.

The spelling of 17215939978031 in words is "seventeen trillion, two hundred fifteen billion, nine hundred thirty-nine million, nine hundred seventy-eight thousand, thirty-one".