1620115613 has 2 divisors, whose sum is σ = 1620115614. Its totient is φ = 1620115612.

The previous prime is 1620115577. The next prime is 1620115619. The reversal of 1620115613 is 3165110261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1005968089 + 614147524 = 31717^2 + 24782^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620115613 - 2²⁸ = 1351680157 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1620115619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810057806 + 810057807.

It is an arithmetic number, because the mean of its divisors is an integer number (810057807).

Almost surely, 2^1620115613 is an apocalyptic number.

It is an amenable number.

1620115613 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620115613 is an equidigital number, since it uses as much as digits as its factorization.

1620115613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 1620115613 is about 40250.6597834122. The cubic root of 1620115613 is about 1174.4882305498.

Adding to 1620115613 its reverse (3165110261), we get a palindrome (4785225874).

The spelling of 1620115613 in words is "one billion, six hundred twenty million, one hundred fifteen thousand, six hundred thirteen".