161500819 has 16 divisors (see below), whose sum is σ = 171908352. Its totient is φ = 151508448.

The previous prime is 161500813. The next prime is 161500841. The reversal of 161500819 is 918005161.

It is a cyclic number.

It is not a de Polignac number, because 161500819 - 2³ = 161500811 is a prime.

It is a super-2 number, since 2×161500819² = 52165029075341522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161500811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 131442 + ... + 132664.

It is an arithmetic number, because the mean of its divisors is an integer number (10744272).

Almost surely, 2^161500819 is an apocalyptic number.

161500819 is a deficient number, since it is larger than the sum of its proper divisors (10407533).

161500819 is a wasteful number, since it uses less digits than its factorization.

161500819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1386.

The product of its (nonzero) digits is 2160, while the sum is 31.

The square root of 161500819 is about 12708.2972502220. The cubic root of 161500819 is about 544.5756807225.

The spelling of 161500819 in words is "one hundred sixty-one million, five hundred thousand, eight hundred nineteen".