1315225155221 has 2 divisors, whose sum is σ = 1315225155222. Its totient is φ = 1315225155220.

The previous prime is 1315225155169. The next prime is 1315225155271. The reversal of 1315225155221 is 1225515225131.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 870462876196 + 444762279025 = 932986^2 + 666905^2 .

It is an emirp because it is prime and its reverse (1225515225131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1315225155221 - 2⁶ = 1315225155157 is a prime.

It is a super-2 number, since 2×1315225155221² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1315225155271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 657612577610 + 657612577611.

It is an arithmetic number, because the mean of its divisors is an integer number (657612577611).

Almost surely, 2^{1315225155221} is an apocalyptic number.

It is an amenable number.

1315225155221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1315225155221 is an equidigital number, since it uses as much as digits as its factorization.

1315225155221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30000, while the sum is 35.

The spelling of 1315225155221 in words is "one trillion, three hundred fifteen billion, two hundred twenty-five million, one hundred fifty-five thousand, two hundred twenty-one".