645622433 has 2 divisors, whose sum is σ = 645622434. Its totient is φ = 645622432.

The previous prime is 645622423. The next prime is 645622477. The reversal of 645622433 is 334226546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 475763344 + 169859089 = 21812^2 + 13033^2 .

It is a cyclic number.

It is not a de Polignac number, because 645622433 - 2¹⁰ = 645621409 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 645622393 and 645622402.

It is not a weakly prime, because it can be changed into another prime (645622403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322811216 + 322811217.

It is an arithmetic number, because the mean of its divisors is an integer number (322811217).

Almost surely, 2^645622433 is an apocalyptic number.

It is an amenable number.

645622433 is a deficient number, since it is larger than the sum of its proper divisors (1).

645622433 is an equidigital number, since it uses as much as digits as its factorization.

645622433 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 35.

The square root of 645622433 is about 25409.1013811980. The cubic root of 645622433 is about 864.2900979336.

Adding to 645622433 its reverse (334226546), we get a palindrome (979848979).

The spelling of 645622433 in words is "six hundred forty-five million, six hundred twenty-two thousand, four hundred thirty-three".