161619666839 has 2 divisors, whose sum is σ = 161619666840. Its totient is φ = 161619666838.

The previous prime is 161619666781. The next prime is 161619666863. The reversal of 161619666839 is 938666916161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161619666839 - 2⁸ = 161619666583 is a prime.

It is a super-2 number, since 2×161619666839² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161619666889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80809833419 + 80809833420.

It is an arithmetic number, because the mean of its divisors is an integer number (80809833420).

Almost surely, 2^161619666839 is an apocalyptic number.

161619666839 is a deficient number, since it is larger than the sum of its proper divisors (1).

161619666839 is an equidigital number, since it uses as much as digits as its factorization.

161619666839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15116544, while the sum is 62.

The spelling of 161619666839 in words is "one hundred sixty-one billion, six hundred nineteen million, six hundred sixty-six thousand, eight hundred thirty-nine".