1620165625 has 48 divisors (see below), whose sum is σ = 2296728000. Its totient is φ = 1132920000.

The previous prime is 1620165619. The next prime is 1620165647. The reversal of 1620165625 is 5265610261.

It is not a de Polignac number, because 1620165625 - 2¹⁷ = 1620034553 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 770826 + ... + 772924.

It is an arithmetic number, because the mean of its divisors is an integer number (47848500).

Almost surely, 2^1620165625 is an apocalyptic number.

It is an amenable number.

1620165625 is a deficient number, since it is larger than the sum of its proper divisors (676562375).

1620165625 is an equidigital number, since it uses as much as digits as its factorization.

1620165625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2156 (or 2136 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 1620165625 is about 40251.2810355149. The cubic root of 1620165625 is about 1174.5003156752.

Adding to 1620165625 its reverse (5265610261), we get a palindrome (6885775886).

The spelling of 1620165625 in words is "one billion, six hundred twenty million, one hundred sixty-five thousand, six hundred twenty-five".