645656411 has 4 divisors (see below), whose sum is σ = 656599800. Its totient is φ = 634713024.

The previous prime is 645656393. The next prime is 645656449. The reversal of 645656411 is 114656546.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645656411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645656491) 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, 5471606 + ... + 5471723.

It is an arithmetic number, because the mean of its divisors is an integer number (164149950).

Almost surely, 2^645656411 is an apocalyptic number.

645656411 is a deficient number, since it is larger than the sum of its proper divisors (10943389).

645656411 is a wasteful number, since it uses less digits than its factorization.

645656411 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10943388.

The product of its digits is 86400, while the sum is 38.

The square root of 645656411 is about 25409.7699910881. The cubic root of 645656411 is about 864.3052597022.

The spelling of 645656411 in words is "six hundred forty-five million, six hundred fifty-six thousand, four hundred eleven".