155045217 has 4 divisors (see below), whose sum is σ = 206726960. Its totient is φ = 103363476.

The previous prime is 155045213. The next prime is 155045239. The reversal of 155045217 is 712540551.

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, and also an emirpimes, since its reverse is a distinct semiprime: 712540551 = 3 ⋅237513517.

It is not a de Polignac number, because 155045217 - 2² = 155045213 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155045213) 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, 25840867 + ... + 25840872.

It is an arithmetic number, because the mean of its divisors is an integer number (51681740).

Almost surely, 2^155045217 is an apocalyptic number.

It is an amenable number.

155045217 is a deficient number, since it is larger than the sum of its proper divisors (51681743).

155045217 is an equidigital number, since it uses as much as digits as its factorization.

155045217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51681742.

The product of its (nonzero) digits is 7000, while the sum is 30.

The square root of 155045217 is about 12451.7154239888. The cubic root of 155045217 is about 537.2207651464.

Adding to 155045217 its reverse (712540551), we get a palindrome (867585768).

The spelling of 155045217 in words is "one hundred fifty-five million, forty-five thousand, two hundred seventeen".