161915109497 has 2 divisors, whose sum is σ = 161915109498. Its totient is φ = 161915109496.

The previous prime is 161915109469. The next prime is 161915109541. The reversal of 161915109497 is 794901519161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 160649457721 + 1265651776 = 400811^2 + 35576^2 .

It is a cyclic number.

It is not a de Polignac number, because 161915109497 - 2¹⁴ = 161915093113 is a prime.

It is not a weakly prime, because it can be changed into another prime (161915108497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80957554748 + 80957554749.

It is an arithmetic number, because the mean of its divisors is an integer number (80957554749).

Almost surely, 2^161915109497 is an apocalyptic number.

It is an amenable number.

161915109497 is a deficient number, since it is larger than the sum of its proper divisors (1).

161915109497 is an equidigital number, since it uses as much as digits as its factorization.

161915109497 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 612360, while the sum is 53.

The spelling of 161915109497 in words is "one hundred sixty-one billion, nine hundred fifteen million, one hundred nine thousand, four hundred ninety-seven".