1620225613 has 12 divisors (see below), whose sum is σ = 1724013760. Its totient is φ = 1522372032.

The previous prime is 1620225601. The next prime is 1620225617. The reversal of 1620225613 is 3165220261.

It is a de Polignac number, because none of the positive numbers 2^k-1620225613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620225617) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181468 + ... + 190186.

Almost surely, 2^1620225613 is an apocalyptic number.

It is an amenable number.

1620225613 is a deficient number, since it is larger than the sum of its proper divisors (103788147).

1620225613 is an equidigital number, since it uses as much as digits as its factorization.

1620225613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9396 (or 9379 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 1620225613 is about 40252.0261974475. The cubic root of 1620225613 is about 1174.5148111182.

Adding to 1620225613 its reverse (3165220261), we get a palindrome (4785445874).

The spelling of 1620225613 in words is "one billion, six hundred twenty million, two hundred twenty-five thousand, six hundred thirteen".