645836241 has 4 divisors (see below), whose sum is σ = 861114992. Its totient is φ = 430557492.

The previous prime is 645836203. The next prime is 645836263. The reversal of 645836241 is 142638546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 645836241 - 2¹³ = 645828049 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 645836241.

It is not an unprimeable number, because it can be changed into a prime (645836291) 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, 107639371 + ... + 107639376.

It is an arithmetic number, because the mean of its divisors is an integer number (215278748).

Almost surely, 2^645836241 is an apocalyptic number.

It is an amenable number.

645836241 is a deficient number, since it is larger than the sum of its proper divisors (215278751).

645836241 is a wasteful number, since it uses less digits than its factorization.

645836241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215278750.

The product of its digits is 138240, while the sum is 39.

The square root of 645836241 is about 25413.3083442514. The cubic root of 645836241 is about 864.3854951465.

The spelling of 645836241 in words is "six hundred forty-five million, eight hundred thirty-six thousand, two hundred forty-one".