645270739 has 2 divisors, whose sum is σ = 645270740. Its totient is φ = 645270738.

The previous prime is 645270721. The next prime is 645270767. The reversal of 645270739 is 937072546.

645270739 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645270739 - 2¹⁹ = 644746451 is a prime.

It is a super-2 number, since 2×645270739² = 832748653219212242, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 645270695 and 645270704.

It is not a weakly prime, because it can be changed into another prime (645210739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322635369 + 322635370.

It is an arithmetic number, because the mean of its divisors is an integer number (322635370).

Almost surely, 2^645270739 is an apocalyptic number.

645270739 is a deficient number, since it is larger than the sum of its proper divisors (1).

645270739 is an equidigital number, since it uses as much as digits as its factorization.

645270739 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 317520, while the sum is 43.

The square root of 645270739 is about 25402.1798080401. The cubic root of 645270739 is about 864.1331326876.

The spelling of 645270739 in words is "six hundred forty-five million, two hundred seventy thousand, seven hundred thirty-nine".