1620225617 has 2 divisors, whose sum is σ = 1620225618. Its totient is φ = 1620225616.

The previous prime is 1620225601. The next prime is 1620225619. The reversal of 1620225617 is 7165220261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1613548561 + 6677056 = 40169^2 + 2584^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620225617 - 2⁴ = 1620225601 is a prime.

Together with 1620225619, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1620225619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810112808 + 810112809.

It is an arithmetic number, because the mean of its divisors is an integer number (810112809).

Almost surely, 2^1620225617 is an apocalyptic number.

It is an amenable number.

1620225617 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620225617 is an equidigital number, since it uses as much as digits as its factorization.

1620225617 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 1620225617 is about 40252.0262471344. The cubic root of 1620225617 is about 1174.5148120847.

Adding to 1620225617 its reverse (7165220261), we get a palindrome (8785445878).

The spelling of 1620225617 in words is "one billion, six hundred twenty million, two hundred twenty-five thousand, six hundred seventeen".