161909375 has 24 divisors (see below), whose sum is σ = 204174432. Its totient is φ = 128380000.

The previous prime is 161909353. The next prime is 161909383. The reversal of 161909375 is 573909161.

It is not a de Polignac number, because 161909375 - 2¹² = 161905279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 615494 + ... + 615756.

It is an arithmetic number, because the mean of its divisors is an integer number (8507268).

Almost surely, 2^161909375 is an apocalyptic number.

161909375 is a deficient number, since it is larger than the sum of its proper divisors (42265057).

161909375 is an frugal number, since it uses more digits than its factorization.

161909375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485 (or 465 counting only the distinct ones).

The product of its (nonzero) digits is 51030, while the sum is 41.

The square root of 161909375 is about 12724.3614771037. The cubic root of 161909375 is about 545.0345066949.

The spelling of 161909375 in words is "one hundred sixty-one million, nine hundred nine thousand, three hundred seventy-five".