161399433506 has 8 divisors (see below), whose sum is σ = 242108020224. Its totient is φ = 80696760100.

The previous prime is 161399433499. The next prime is 161399433541. The reversal of 161399433506 is 605334993161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1409450 + ... + 1519653.

It is an arithmetic number, because the mean of its divisors is an integer number (30263502528).

Almost surely, 2^161399433506 is an apocalyptic number.

161399433506 is a deficient number, since it is larger than the sum of its proper divisors (80708586718).

161399433506 is a wasteful number, since it uses less digits than its factorization.

161399433506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2956656.

The product of its (nonzero) digits is 1574640, while the sum is 50.

The spelling of 161399433506 in words is "one hundred sixty-one billion, three hundred ninety-nine million, four hundred thirty-three thousand, five hundred six".