161728920319 has 8 divisors (see below), whose sum is σ = 164918257920. Its totient is φ = 158554521816.

The previous prime is 161728920293. The next prime is 161728920377. The reversal of 161728920319 is 913029827161.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 161728920319 - 2²⁹ = 161192049407 is a prime.

It is a super-2 number, since 2×161728920319² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161728920389) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3712909 + ... + 3756214.

It is an arithmetic number, because the mean of its divisors is an integer number (20614782240).

Almost surely, 2^161728920319 is an apocalyptic number.

161728920319 is a deficient number, since it is larger than the sum of its proper divisors (3189337601).

161728920319 is an equidigital number, since it uses as much as digits as its factorization.

161728920319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7469549.

The product of its (nonzero) digits is 326592, while the sum is 49.

The spelling of 161728920319 in words is "one hundred sixty-one billion, seven hundred twenty-eight million, nine hundred twenty thousand, three hundred nineteen".