161999339 has 4 divisors (see below), whose sum is σ = 170525640. Its totient is φ = 153473040.

The previous prime is 161999311. The next prime is 161999353. The reversal of 161999339 is 933999161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 933999161 = 9011 ⋅103651.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161999339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161999359) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4263122 + ... + 4263159.

It is an arithmetic number, because the mean of its divisors is an integer number (42631410).

Almost surely, 2^161999339 is an apocalyptic number.

161999339 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

161999339 is a deficient number, since it is larger than the sum of its proper divisors (8526301).

161999339 is an equidigital number, since it uses as much as digits as its factorization.

161999339 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8526300.

The product of its digits is 354294, while the sum is 50.

The square root of 161999339 is about 12727.8960947990. The cubic root of 161999339 is about 545.1354364186.

The spelling of 161999339 in words is "one hundred sixty-one million, nine hundred ninety-nine thousand, three hundred thirty-nine".