642817027 has 2 divisors, whose sum is σ = 642817028. Its totient is φ = 642817026.

The previous prime is 642817013. The next prime is 642817051. The reversal of 642817027 is 720718246.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642817027 is a prime.

It is a super-2 number, since 2×642817027² = 826427460402237458, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (642817057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321408513 + 321408514.

It is an arithmetic number, because the mean of its divisors is an integer number (321408514).

Almost surely, 2^642817027 is an apocalyptic number.

642817027 is a deficient number, since it is larger than the sum of its proper divisors (1).

642817027 is an equidigital number, since it uses as much as digits as its factorization.

642817027 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 37632, while the sum is 37.

The square root of 642817027 is about 25353.8365341421. The cubic root of 642817027 is about 863.0364213895.

The spelling of 642817027 in words is "six hundred forty-two million, eight hundred seventeen thousand, twenty-seven".