161913619 has 8 divisors (see below), whose sum is σ = 189347840. Its totient is φ = 135555336.

The previous prime is 161913617. The next prime is 161913643. The reversal of 161913619 is 916319161.

161913619 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 161913619 - 2¹ = 161913617 is a prime.

It is a super-3 number, since 3×161913619³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161913613) 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, 268659 + ... + 269260.

It is an arithmetic number, because the mean of its divisors is an integer number (23668480).

Almost surely, 2^161913619 is an apocalyptic number.

161913619 is a deficient number, since it is larger than the sum of its proper divisors (27434221).

161913619 is an equidigital number, since it uses as much as digits as its factorization.

161913619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 537969.

The product of its digits is 8748, while the sum is 37.

The square root of 161913619 is about 12724.5282427287. The cubic root of 161913619 is about 545.0392688367.

The spelling of 161913619 in words is "one hundred sixty-one million, nine hundred thirteen thousand, six hundred nineteen".