645372522785 has 8 divisors (see below), whose sum is σ = 774537036840. Its totient is φ = 516238011904.

The previous prime is 645372522763. The next prime is 645372522827. The reversal of 645372522785 is 587225273546.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5590104289 + 639782418496 = 74767^2 + 799864^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 645372522785 - 2¹² = 645372518689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645372522785.

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, 7453442 + ... + 7539531.

It is an arithmetic number, because the mean of its divisors is an integer number (96817129605).

Almost surely, 2^645372522785 is an apocalyptic number.

It is an amenable number.

645372522785 is a deficient number, since it is larger than the sum of its proper divisors (129164514055).

645372522785 is a wasteful number, since it uses less digits than its factorization.

645372522785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15001587.

The product of its digits is 28224000, while the sum is 56.

The spelling of 645372522785 in words is "six hundred forty-five billion, three hundred seventy-two million, five hundred twenty-two thousand, seven hundred eighty-five".