642884573 has 2 divisors, whose sum is σ = 642884574. Its totient is φ = 642884572.

The previous prime is 642884533. The next prime is 642884587. The reversal of 642884573 is 375488246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 555686329 + 87198244 = 23573^2 + 9338^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642884573 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642884533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321442286 + 321442287.

It is an arithmetic number, because the mean of its divisors is an integer number (321442287).

Almost surely, 2^642884573 is an apocalyptic number.

It is an amenable number.

642884573 is a deficient number, since it is larger than the sum of its proper divisors (1).

642884573 is an equidigital number, since it uses as much as digits as its factorization.

642884573 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1290240, while the sum is 47.

The square root of 642884573 is about 25355.1685657974. The cubic root of 642884573 is about 863.0666490769.

The spelling of 642884573 in words is "six hundred forty-two million, eight hundred eighty-four thousand, five hundred seventy-three".