155581261 has 8 divisors (see below), whose sum is σ = 170359200. Its totient is φ = 140909040.

The previous prime is 155581249. The next prime is 155581271. The reversal of 155581261 is 162185551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 155581261 - 2⁷ = 155581133 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155581211) 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, 23331 + ... + 29248.

It is an arithmetic number, because the mean of its divisors is an integer number (21294900).

Almost surely, 2^155581261 is an apocalyptic number.

155581261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

155581261 is a deficient number, since it is larger than the sum of its proper divisors (14777939).

155581261 is a wasteful number, since it uses less digits than its factorization.

155581261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52859.

The product of its digits is 12000, while the sum is 34.

The square root of 155581261 is about 12473.2217570281. The cubic root of 155581261 is about 537.8391712578.

The spelling of 155581261 in words is "one hundred fifty-five million, five hundred eighty-one thousand, two hundred sixty-one".