646315613 has 2 divisors, whose sum is σ = 646315614. Its totient is φ = 646315612.

The previous prime is 646315601. The next prime is 646315633. The reversal of 646315613 is 316513646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 554979364 + 91336249 = 23558^2 + 9557^2 .

It is a cyclic number.

It is not a de Polignac number, because 646315613 - 2¹² = 646311517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646315633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323157806 + 323157807.

It is an arithmetic number, because the mean of its divisors is an integer number (323157807).

Almost surely, 2^646315613 is an apocalyptic number.

It is an amenable number.

646315613 is a deficient number, since it is larger than the sum of its proper divisors (1).

646315613 is an equidigital number, since it uses as much as digits as its factorization.

646315613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 35.

The square root of 646315613 is about 25422.7381098103. The cubic root of 646315613 is about 864.5993056552.

The spelling of 646315613 in words is "six hundred forty-six million, three hundred fifteen thousand, six hundred thirteen".