161788399 has 2 divisors, whose sum is σ = 161788400. Its totient is φ = 161788398.

The previous prime is 161788397. The next prime is 161788423. The reversal of 161788399 is 993887161.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161788399 - 2¹ = 161788397 is a prime.

Together with 161788397, 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 (161788397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80894199 + 80894200.

It is an arithmetic number, because the mean of its divisors is an integer number (80894200).

Almost surely, 2^161788399 is an apocalyptic number.

161788399 is a deficient number, since it is larger than the sum of its proper divisors (1).

161788399 is an equidigital number, since it uses as much as digits as its factorization.

161788399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653184, while the sum is 52.

The square root of 161788399 is about 12719.6068728558. The cubic root of 161788399 is about 544.8987259566.

The spelling of 161788399 in words is "one hundred sixty-one million, seven hundred eighty-eight thousand, three hundred ninety-nine".