161933639 has 16 divisors (see below), whose sum is σ = 193548288. Its totient is φ = 132466752.

The previous prime is 161933623. The next prime is 161933669. The reversal of 161933639 is 936339161.

It is a happy number.

It is not a de Polignac number, because 161933639 - 2⁴ = 161933623 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 161933596 and 161933605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161933669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 96899 + ... + 98555.

It is an arithmetic number, because the mean of its divisors is an integer number (12096768).

Almost surely, 2^161933639 is an apocalyptic number.

161933639 is a deficient number, since it is larger than the sum of its proper divisors (31614649).

161933639 is a wasteful number, since it uses less digits than its factorization.

161933639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2294.

The product of its digits is 78732, while the sum is 41.

The square root of 161933639 is about 12725.3148880489. The cubic root of 161933639 is about 545.0617319183.

The spelling of 161933639 in words is "one hundred sixty-one million, nine hundred thirty-three thousand, six hundred thirty-nine".