161720610 has 16 divisors (see below), whose sum is σ = 388129536. Its totient is φ = 43125488.

The previous prime is 161720509. The next prime is 161720621. The reversal of 161720610 is 16027161.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2695314 + ... + 2695373.

It is an arithmetic number, because the mean of its divisors is an integer number (24258096).

Almost surely, 2^161720610 is an apocalyptic number.

161720610 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161720610 is an abundant number, since it is smaller than the sum of its proper divisors (226408926).

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

161720610 is a wasteful number, since it uses less digits than its factorization.

161720610 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5390697.

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 161720610 is about 12716.9418493599. The cubic root of 161720610 is about 544.8226115171.

Adding to 161720610 its reverse (16027161), we get a palindrome (177747771).

The spelling of 161720610 in words is "one hundred sixty-one million, seven hundred twenty thousand, six hundred ten".