161577 has 12 divisors (see below), whose sum is σ = 251524. Its totient is φ = 99360.

The previous prime is 161573. The next prime is 161591. The reversal of 161577 is 775161.

It can be written as a sum of positive squares in 2 ways, for example, as 46656 + 114921 = 216^2 + 339^2 .

It is not a de Polignac number, because 161577 - 2² = 161573 is a prime.

It is a super-2 number, since 2×161577² = 52214253858, which contains 22 as substring.

161577 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 161577.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161573) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 574 + ... + 807.

2¹⁶¹⁵⁷⁷ is an apocalyptic number.

It is an amenable number.

161577 is a deficient number, since it is larger than the sum of its proper divisors (89947).

161577 is a wasteful number, since it uses less digits than its factorization.

161577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1400 (or 1397 counting only the distinct ones).

The product of its digits is 1470, while the sum is 27.

The square root of 161577 is about 401.9664165076. The cubic root of 161577 is about 54.4661293908.

Adding to 161577 its sum of digits (27), we get a square (161604 = 402²).

The spelling of 161577 in words is "one hundred sixty-one thousand, five hundred seventy-seven".