161872619 has 4 divisors (see below), whose sum is σ = 161910000. Its totient is φ = 161835240.

The previous prime is 161872573. The next prime is 161872631. The reversal of 161872619 is 916278161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161872619 - 2⁸ = 161872363 is a prime.

It is a super-2 number, since 2×161872619² = 52405489563838322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161872649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11192 + ... + 21189.

It is an arithmetic number, because the mean of its divisors is an integer number (40477500).

Almost surely, 2^161872619 is an apocalyptic number.

161872619 is a deficient number, since it is larger than the sum of its proper divisors (37381).

161872619 is an equidigital number, since it uses as much as digits as its factorization.

161872619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37380.

The product of its digits is 36288, while the sum is 41.

The square root of 161872619 is about 12722.9170790350. The cubic root of 161872619 is about 544.9932597433.

The spelling of 161872619 in words is "one hundred sixty-one million, eight hundred seventy-two thousand, six hundred nineteen".