155581385 has 4 divisors (see below), whose sum is σ = 186697668. Its totient is φ = 124465104.

The previous prime is 155581379. The next prime is 155581409. The reversal of 155581385 is 583185551.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 112126921 + 43454464 = 10589^2 + 6592^2 .

It is a cyclic number.

It is not a de Polignac number, because 155581385 - 2⁴ = 155581369 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15558134 + ... + 15558143.

It is an arithmetic number, because the mean of its divisors is an integer number (46674417).

Almost surely, 2^155581385 is an apocalyptic number.

It is an amenable number.

155581385 is a deficient number, since it is larger than the sum of its proper divisors (31116283).

155581385 is an equidigital number, since it uses as much as digits as its factorization.

155581385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31116282.

The product of its digits is 120000, while the sum is 41.

The square root of 155581385 is about 12473.2267276756. The cubic root of 155581385 is about 537.8393141457.

The spelling of 155581385 in words is "one hundred fifty-five million, five hundred eighty-one thousand, three hundred eighty-five".