155222581 has 4 divisors (see below), whose sum is σ = 155381472. Its totient is φ = 155063692.

The previous prime is 155222527. The next prime is 155222593. The reversal of 155222581 is 185222551.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 155222581 - 2⁹ = 155222069 is a prime.

It is a super-2 number, since 2×155222581² = 48188099304603122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155222521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77971 + ... + 79936.

It is an arithmetic number, because the mean of its divisors is an integer number (38845368).

Almost surely, 2^155222581 is an apocalyptic number.

It is an amenable number.

155222581 is a deficient number, since it is larger than the sum of its proper divisors (158891).

155222581 is an equidigital number, since it uses as much as digits as its factorization.

155222581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158890.

The product of its digits is 8000, while the sum is 31.

The square root of 155222581 is about 12458.8354592233. The cubic root of 155222581 is about 537.4255383420.

The spelling of 155222581 in words is "one hundred fifty-five million, two hundred twenty-two thousand, five hundred eighty-one".