642841547057 has 2 divisors, whose sum is σ = 642841547058. Its totient is φ = 642841547056.

The previous prime is 642841547021. The next prime is 642841547099. The reversal of 642841547057 is 750745148246.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 523598407201 + 119243139856 = 723601^2 + 345316^2 .

It is a cyclic number.

It is not a de Polignac number, because 642841547057 - 2¹⁴ = 642841530673 is a prime.

It is a super-2 number, since 2×642841547057² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (642841544057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321420773528 + 321420773529.

It is an arithmetic number, because the mean of its divisors is an integer number (321420773529).

Almost surely, 2^642841547057 is an apocalyptic number.

It is an amenable number.

642841547057 is a deficient number, since it is larger than the sum of its proper divisors (1).

642841547057 is an equidigital number, since it uses as much as digits as its factorization.

642841547057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7526400, while the sum is 53.

The spelling of 642841547057 in words is "six hundred forty-two billion, eight hundred forty-one million, five hundred forty-seven thousand, fifty-seven".