1645640470265 has 12 divisors (see below), whose sum is σ = 2170613381412. Its totient is φ = 1196829432480.

The previous prime is 1645640470261. The next prime is 1645640470267. The reversal of 1645640470265 is 5620740465461.

It can be written as a sum of positive squares in 2 ways, for example, as 320772711424 + 1324867758841 = 566368^2 + 1151029^2 .

It is not a de Polignac number, because 1645640470265 - 2² = 1645640470261 is a prime.

It is a hoax number, since the sum of its digits (50) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1645640470261) 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, 1360032842 + ... + 1360034051.

It is an arithmetic number, because the mean of its divisors is an integer number (180884448451).

Almost surely, 2^{1645640470265} is an apocalyptic number.

It is an amenable number.

1645640470265 is a deficient number, since it is larger than the sum of its proper divisors (524972911147).

1645640470265 is a wasteful number, since it uses less digits than its factorization.

1645640470265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2720066920 (or 2720066909 counting only the distinct ones).

The product of its (nonzero) digits is 4838400, while the sum is 50.

The spelling of 1645640470265 in words is "one trillion, six hundred forty-five billion, six hundred forty million, four hundred seventy thousand, two hundred sixty-five".