645274555241 has 4 divisors (see below), whose sum is σ = 645277220052. Its totient is φ = 645271890432.

The previous prime is 645274555229. The next prime is 645274555259. The reversal of 645274555241 is 142555472546.

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 355658369641 + 289616185600 = 596371^2 + 538160^2 .

It is a cyclic number.

It is not a de Polignac number, because 645274555241 - 2²² = 645270360937 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 645274555241.

It is not an unprimeable number, because it can be changed into a prime (645274555201) 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, 928340 + ... + 1467093.

It is an arithmetic number, because the mean of its divisors is an integer number (161319305013).

Almost surely, 2^645274555241 is an apocalyptic number.

It is an amenable number.

645274555241 is a deficient number, since it is larger than the sum of its proper divisors (2664811).

645274555241 is a wasteful number, since it uses less digits than its factorization.

645274555241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2664810.

The product of its digits is 6720000, while the sum is 50.

The spelling of 645274555241 in words is "six hundred forty-five billion, two hundred seventy-four million, five hundred fifty-five thousand, two hundred forty-one".