645260563405 has 4 divisors (see below), whose sum is σ = 774312676092. Its totient is φ = 516208450720.

The previous prime is 645260563391. The next prime is 645260563411. The reversal of 645260563405 is 504365062546.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 322838739721 + 322421823684 = 568189^2 + 567822^2 .

It is not a de Polignac number, because 645260563405 - 2¹¹ = 645260561357 is a prime.

It is a super-2 number, since 2×645260563405² (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 3 ways as a sum of consecutive naturals, for example, 64526056336 + ... + 64526056345.

It is an arithmetic number, because the mean of its divisors is an integer number (193578169023).

Almost surely, 2^645260563405 is an apocalyptic number.

It is an amenable number.

645260563405 is a deficient number, since it is larger than the sum of its proper divisors (129052112687).

645260563405 is a wasteful number, since it uses less digits than its factorization.

645260563405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129052112686.

The product of its (nonzero) digits is 2592000, while the sum is 46.

The spelling of 645260563405 in words is "six hundred forty-five billion, two hundred sixty million, five hundred sixty-three thousand, four hundred five".