645115447 has 2 divisors, whose sum is σ = 645115448. Its totient is φ = 645115446.

The previous prime is 645115441. The next prime is 645115459. The reversal of 645115447 is 744511546.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645115447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645115441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322557723 + 322557724.

It is an arithmetic number, because the mean of its divisors is an integer number (322557724).

Almost surely, 2^645115447 is an apocalyptic number.

645115447 is a deficient number, since it is larger than the sum of its proper divisors (1).

645115447 is an equidigital number, since it uses as much as digits as its factorization.

645115447 is an evil number, because the sum of its binary digits is even.

The product of its digits is 67200, while the sum is 37.

The square root of 645115447 is about 25399.1229572991. The cubic root of 645115447 is about 864.0638058553.

The spelling of 645115447 in words is "six hundred forty-five million, one hundred fifteen thousand, four hundred forty-seven".