645264295765 has 8 divisors (see below), whose sum is σ = 774363646368. Its totient is φ = 516180442320.

The previous prime is 645264295751. The next prime is 645264295771. The reversal of 645264295765 is 567592462546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 645264295765 - 2¹³ = 645264287573 is a prime.

It is a super-2 number, since 2×645264295765² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3782487 + ... + 3949396.

It is an arithmetic number, because the mean of its divisors is an integer number (96795455796).

Almost surely, 2^645264295765 is an apocalyptic number.

It is an amenable number.

645264295765 is a deficient number, since it is larger than the sum of its proper divisors (129099350603).

645264295765 is a wasteful number, since it uses less digits than its factorization.

645264295765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7748579.

The product of its digits is 108864000, while the sum is 61.

The spelling of 645264295765 in words is "six hundred forty-five billion, two hundred sixty-four million, two hundred ninety-five thousand, seven hundred sixty-five".