645002653 has 2 divisors, whose sum is σ = 645002654. Its totient is φ = 645002652.

The previous prime is 645002651. The next prime is 645002663. The reversal of 645002653 is 356200546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 401080729 + 243921924 = 20027^2 + 15618^2 .

It is a cyclic number.

It is not a de Polignac number, because 645002653 - 2¹ = 645002651 is a prime.

Together with 645002651, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645002651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322501326 + 322501327.

It is an arithmetic number, because the mean of its divisors is an integer number (322501327).

Almost surely, 2^645002653 is an apocalyptic number.

It is an amenable number.

645002653 is a deficient number, since it is larger than the sum of its proper divisors (1).

645002653 is an equidigital number, since it uses as much as digits as its factorization.

645002653 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 31.

The square root of 645002653 is about 25396.9024292334. The cubic root of 645002653 is about 864.0134443817.

The spelling of 645002653 in words is "six hundred forty-five million, two thousand, six hundred fifty-three".