161995439 has 4 divisors (see below), whose sum is σ = 162039480. Its totient is φ = 161951400.

The previous prime is 161995411. The next prime is 161995441. The reversal of 161995439 is 934599161.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161995439 - 2¹² = 161991343 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 161995393 and 161995402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161995459) 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, 15944 + ... + 24045.

It is an arithmetic number, because the mean of its divisors is an integer number (40509870).

Almost surely, 2^161995439 is an apocalyptic number.

161995439 is a deficient number, since it is larger than the sum of its proper divisors (44041).

161995439 is an equidigital number, since it uses as much as digits as its factorization.

161995439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44040.

The product of its digits is 262440, while the sum is 47.

The square root of 161995439 is about 12727.7428870951. The cubic root of 161995439 is about 545.1310618220.

The spelling of 161995439 in words is "one hundred sixty-one million, nine hundred ninety-five thousand, four hundred thirty-nine".