642642629 has 2 divisors, whose sum is σ = 642642630. Its totient is φ = 642642628.

The previous prime is 642642587. The next prime is 642642631. The reversal of 642642629 is 926246246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 548028100 + 94614529 = 23410^2 + 9727^2 .

It is a cyclic number.

It is not a de Polignac number, because 642642629 - 2⁸ = 642642373 is a prime.

Together with 642642631, 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 (642642829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321321314 + 321321315.

It is an arithmetic number, because the mean of its divisors is an integer number (321321315).

Almost surely, 2^642642629 is an apocalyptic number.

It is an amenable number.

642642629 is a deficient number, since it is larger than the sum of its proper divisors (1).

642642629 is an equidigital number, since it uses as much as digits as its factorization.

642642629 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 41.

The square root of 642642629 is about 25350.3970185873. The cubic root of 642642629 is about 862.9583662909.

The spelling of 642642629 in words is "six hundred forty-two million, six hundred forty-two thousand, six hundred twenty-nine".