642998927 has 2 divisors, whose sum is σ = 642998928. Its totient is φ = 642998926.

The previous prime is 642998911. The next prime is 642998929. The reversal of 642998927 is 729899246.

642998927 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 642998927 - 2⁴ = 642998911 is a prime.

Together with 642998929, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642998929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321499463 + 321499464.

It is an arithmetic number, because the mean of its divisors is an integer number (321499464).

Almost surely, 2^642998927 is an apocalyptic number.

642998927 is a deficient number, since it is larger than the sum of its proper divisors (1).

642998927 is an equidigital number, since it uses as much as digits as its factorization.

642998927 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3919104, while the sum is 56.

The square root of 642998927 is about 25357.4235087085. The cubic root of 642998927 is about 863.1178191088.

The spelling of 642998927 in words is "six hundred forty-two million, nine hundred ninety-eight thousand, nine hundred twenty-seven".