155050216023221 has 2 divisors, whose sum is σ = 155050216023222. Its totient is φ = 155050216023220.

The previous prime is 155050216023211. The next prime is 155050216023239. The reversal of 155050216023221 is 122320612050551.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 126822395787025 + 28227820236196 = 11261545^2 + 5312986^2 .

It is a cyclic number.

It is not a de Polignac number, because 155050216023221 - 2³⁴ = 155033036154037 is a prime.

It is a super-2 number, since 2×155050216023221² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155050216023211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77525108011610 + 77525108011611.

It is an arithmetic number, because the mean of its divisors is an integer number (77525108011611).

Almost surely, 2^{155050216023221} is an apocalyptic number.

It is an amenable number.

155050216023221 is a deficient number, since it is larger than the sum of its proper divisors (1).

155050216023221 is an equidigital number, since it uses as much as digits as its factorization.

155050216023221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36000, while the sum is 35.

Adding to 155050216023221 its reverse (122320612050551), we get a palindrome (277370828073772).

The spelling of 155050216023221 in words is "one hundred fifty-five trillion, fifty billion, two hundred sixteen million, twenty-three thousand, two hundred twenty-one".