1313220521 has 2 divisors, whose sum is σ = 1313220522. Its totient is φ = 1313220520.

The previous prime is 1313220499. The next prime is 1313220527. The reversal of 1313220521 is 1250223131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1102970521 + 210250000 = 33211^2 + 14500^2 .

It is a cyclic number.

It is not a de Polignac number, because 1313220521 - 2²² = 1309026217 is a prime.

It is a super-2 number, since 2×1313220521² = 3449096273551022882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1313220493 and 1313220502.

It is not a weakly prime, because it can be changed into another prime (1313220527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656610260 + 656610261.

It is an arithmetic number, because the mean of its divisors is an integer number (656610261).

Almost surely, 2^1313220521 is an apocalyptic number.

It is an amenable number.

1313220521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1313220521 is an equidigital number, since it uses as much as digits as its factorization.

1313220521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 1313220521 is about 36238.3846356319. The cubic root of 1313220521 is about 1095.0800997819.

Adding to 1313220521 its reverse (1250223131), we get a palindrome (2563443652).

The spelling of 1313220521 in words is "one billion, three hundred thirteen million, two hundred twenty thousand, five hundred twenty-one".