155969 has 6 divisors (see below), whose sum is σ = 171570. Its totient is φ = 141680.

The previous prime is 155921. The next prime is 156007. The reversal of 155969 is 969551.

It can be written as a sum of positive squares in only one way, i.e., 148225 + 7744 = 385^2 + 88^2 .

It is a de Polignac number, because none of the positive numbers 2^k-155969 is a prime.

It is a super-2 number, since 2×155969² = 48652657922, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (155069) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 524 + ... + 765.

It is an arithmetic number, because the mean of its divisors is an integer number (28595).

2¹⁵⁵⁹⁶⁹ is an apocalyptic number.

It is an amenable number.

155969 is a deficient number, since it is larger than the sum of its proper divisors (15601).

155969 is a wasteful number, since it uses less digits than its factorization.

155969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1311 (or 1300 counting only the distinct ones).

The product of its digits is 12150, while the sum is 35.

The square root of 155969 is about 394.9291075624. The cubic root of 155969 is about 53.8285600814.

The spelling of 155969 in words is "one hundred fifty-five thousand, nine hundred sixty-nine".