155225261 has 4 divisors (see below), whose sum is σ = 155254812. Its totient is φ = 155195712.

The previous prime is 155225209. The next prime is 155225263. The reversal of 155225261 is 162522551.

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 34445161 + 120780100 = 5869^2 + 10990^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155225261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155225263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4526 + ... + 18191.

It is an arithmetic number, because the mean of its divisors is an integer number (38813703).

Almost surely, 2^155225261 is an apocalyptic number.

It is an amenable number.

155225261 is a deficient number, since it is larger than the sum of its proper divisors (29551).

155225261 is an equidigital number, since it uses as much as digits as its factorization.

155225261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29550.

The product of its digits is 6000, while the sum is 29.

The square root of 155225261 is about 12458.9430129526. The cubic root of 155225261 is about 537.4286313030.

The spelling of 155225261 in words is "one hundred fifty-five million, two hundred twenty-five thousand, two hundred sixty-one".