642728747 has 2 divisors, whose sum is σ = 642728748. Its totient is φ = 642728746.

The previous prime is 642728731. The next prime is 642728761. The reversal of 642728747 is 747827246.

642728747 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 642728747 - 2⁴ = 642728731 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (642728717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321364373 + 321364374.

It is an arithmetic number, because the mean of its divisors is an integer number (321364374).

Almost surely, 2^642728747 is an apocalyptic number.

642728747 is a deficient number, since it is larger than the sum of its proper divisors (1).

642728747 is an equidigital number, since it uses as much as digits as its factorization.

642728747 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1053696, while the sum is 47.

The square root of 642728747 is about 25352.0955149668. The cubic root of 642728747 is about 862.9969117831.

The spelling of 642728747 in words is "six hundred forty-two million, seven hundred twenty-eight thousand, seven hundred forty-seven".