42421565618 has 4 divisors (see below), whose sum is σ = 63632348430. Its totient is φ = 21210782808.

The previous prime is 42421565611. The next prime is 42421565623. The reversal of 42421565618 is 81656512424.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 28423599649 + 13997965969 = 168593^2 + 118313^2 .

It is not an unprimeable number, because it can be changed into a prime (42421565611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605391403 + ... + 10605391406.

Almost surely, 2^42421565618 is an apocalyptic number.

42421565618 is a deficient number, since it is larger than the sum of its proper divisors (21210782812).

42421565618 is a wasteful number, since it uses less digits than its factorization.

42421565618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21210782811.

The product of its digits is 460800, while the sum is 44.

The spelling of 42421565618 in words is "forty-two billion, four hundred twenty-one million, five hundred sixty-five thousand, six hundred eighteen".