642224431 has 2 divisors, whose sum is σ = 642224432. Its totient is φ = 642224430.

The previous prime is 642224371. The next prime is 642224437. The reversal of 642224431 is 134422246.

642224431 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 642224431 - 2⁹ = 642223919 is a prime.

It is a super-2 number, since 2×642224431² = 824904439546547522, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 642224431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642224437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321112215 + 321112216.

It is an arithmetic number, because the mean of its divisors is an integer number (321112216).

Almost surely, 2^642224431 is an apocalyptic number.

642224431 is a deficient number, since it is larger than the sum of its proper divisors (1).

642224431 is an equidigital number, since it uses as much as digits as its factorization.

642224431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 28.

The square root of 642224431 is about 25342.1473241712. The cubic root of 642224431 is about 862.7711363765.

Adding to 642224431 its reverse (134422246), we get a palindrome (776646677).

The spelling of 642224431 in words is "six hundred forty-two million, two hundred twenty-four thousand, four hundred thirty-one".