642773407 has 2 divisors, whose sum is σ = 642773408. Its totient is φ = 642773406.

The previous prime is 642773353. The next prime is 642773419. The reversal of 642773407 is 704377246.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 642773407 - 2⁷ = 642773279 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 642773407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642773447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321386703 + 321386704.

It is an arithmetic number, because the mean of its divisors is an integer number (321386704).

Almost surely, 2^642773407 is an apocalyptic number.

642773407 is a deficient number, since it is larger than the sum of its proper divisors (1).

642773407 is an equidigital number, since it uses as much as digits as its factorization.

642773407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 197568, while the sum is 40.

The square root of 642773407 is about 25352.9762947075. The cubic root of 642773407 is about 863.0168997638.

The spelling of 642773407 in words is "six hundred forty-two million, seven hundred seventy-three thousand, four hundred seven".