161020506 has 16 divisors (see below), whose sum is σ = 324578304. Its totient is φ = 53250624.

The previous prime is 161020487. The next prime is 161020507. The reversal of 161020506 is 605020161.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (161020507) 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, 104895 + ... + 106418.

It is an arithmetic number, because the mean of its divisors is an integer number (20286144).

Almost surely, 2^161020506 is an apocalyptic number.

161020506 is an abundant number, since it is smaller than the sum of its proper divisors (163557798).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161020506 is a wasteful number, since it uses less digits than its factorization.

161020506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211445.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 161020506 is about 12689.3855643211. The cubic root of 161020506 is about 544.0352778629.

Subtracting from 161020506 its sum of digits (21), we obtain a triangular number (161020485 = T₁₇₉₄₅).

Adding to 161020506 its reverse (605020161), we get a palindrome (766040667).

The spelling of 161020506 in words is "one hundred sixty-one million, twenty thousand, five hundred six".