1645045807 has 4 divisors (see below), whose sum is σ = 1664865720. Its totient is φ = 1625225896.

The previous prime is 1645045799. The next prime is 1645045811. The reversal of 1645045807 is 7085405461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7085405461 = 23 ⋅308061107.

It is a cyclic number.

It is not a de Polignac number, because 1645045807 - 2³ = 1645045799 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1645045807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645045607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9909832 + ... + 9909997.

It is an arithmetic number, because the mean of its divisors is an integer number (416216430).

Almost surely, 2^1645045807 is an apocalyptic number.

1645045807 is a deficient number, since it is larger than the sum of its proper divisors (19819913).

1645045807 is an equidigital number, since it uses as much as digits as its factorization.

1645045807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19819912.

The product of its (nonzero) digits is 134400, while the sum is 40.

The square root of 1645045807 is about 40559.1642788655. The cubic root of 1645045807 is about 1180.4818981157.

The spelling of 1645045807 in words is "one billion, six hundred forty-five million, forty-five thousand, eight hundred seven".