161920761 has 8 divisors (see below), whose sum is σ = 215957184. Its totient is φ = 107915760.

The previous prime is 161920753. The next prime is 161920763. The reversal of 161920761 is 167029161.

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

It is not a de Polignac number, because 161920761 - 2³ = 161920753 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (161920763) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 9916 + ... + 20546.

It is an arithmetic number, because the mean of its divisors is an integer number (26994648).

Almost surely, 2^161920761 is an apocalyptic number.

It is an amenable number.

161920761 is a deficient number, since it is larger than the sum of its proper divisors (54036423).

161920761 is a wasteful number, since it uses less digits than its factorization.

161920761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15711.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 161920761 is about 12724.8088787219. The cubic root of 161920761 is about 545.0472826020.

The spelling of 161920761 in words is "one hundred sixty-one million, nine hundred twenty thousand, seven hundred sixty-one".