42018815557 has 2 divisors, whose sum is σ = 42018815558. Its totient is φ = 42018815556.

The previous prime is 42018815479. The next prime is 42018815563. The reversal of 42018815557 is 75551881024.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40363220836 + 1655594721 = 200906^2 + 40689^2 .

It is a cyclic number.

It is not a de Polignac number, because 42018815557 - 2¹¹ = 42018813509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42018915557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21009407778 + 21009407779.

It is an arithmetic number, because the mean of its divisors is an integer number (21009407779).

Almost surely, 2^42018815557 is an apocalyptic number.

It is an amenable number.

42018815557 is a deficient number, since it is larger than the sum of its proper divisors (1).

42018815557 is an equidigital number, since it uses as much as digits as its factorization.

42018815557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448000, while the sum is 46.

The spelling of 42018815557 in words is "forty-two billion, eighteen million, eight hundred fifteen thousand, five hundred fifty-seven".