155220713 has 4 divisors (see below), whose sum is σ = 156078468. Its totient is φ = 154362960.

The previous prime is 155220683. The next prime is 155220733. The reversal of 155220713 is 317022551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 317022551 = 61 ⋅5197091.

It can be written as a sum of positive squares in 2 ways, for example, as 14845609 + 140375104 = 3853^2 + 11848^2 .

It is a cyclic number.

It is not a de Polignac number, because 155220713 - 2¹⁶ = 155155177 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (155220733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 428606 + ... + 428967.

It is an arithmetic number, because the mean of its divisors is an integer number (39019617).

Almost surely, 2^155220713 is an apocalyptic number.

It is an amenable number.

155220713 is a deficient number, since it is larger than the sum of its proper divisors (857755).

155220713 is an equidigital number, since it uses as much as digits as its factorization.

155220713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 857754.

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 155220713 is about 12458.7604921196. The cubic root of 155220713 is about 537.4233824810.

The spelling of 155220713 in words is "one hundred fifty-five million, two hundred twenty thousand, seven hundred thirteen".