315523321 has 2 divisors, whose sum is σ = 315523322. Its totient is φ = 315523320.

The previous prime is 315523319. The next prime is 315523333. The reversal of 315523321 is 123325513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 309372921 + 6150400 = 17589^2 + 2480^2 .

It is a cyclic number.

It is not a de Polignac number, because 315523321 - 2¹ = 315523319 is a prime.

Together with 315523319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (315523391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157761660 + 157761661.

It is an arithmetic number, because the mean of its divisors is an integer number (157761661).

Almost surely, 2^315523321 is an apocalyptic number.

It is an amenable number.

315523321 is a deficient number, since it is larger than the sum of its proper divisors (1).

315523321 is an equidigital number, since it uses as much as digits as its factorization.

315523321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2700, while the sum is 25.

The square root of 315523321 is about 17762.9761301422. The cubic root of 315523321 is about 680.7857993471.

Adding to 315523321 its reverse (123325513), we get a palindrome (438848834).

It can be divided in two parts, 315523 and 321, that added together give a square (315844 = 562²).

The spelling of 315523321 in words is "three hundred fifteen million, five hundred twenty-three thousand, three hundred twenty-one".