42165554491 has 2 divisors, whose sum is σ = 42165554492. Its totient is φ = 42165554490.

The previous prime is 42165554443. The next prime is 42165554579. The reversal of 42165554491 is 19445556124.

42165554491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42165554491 - 2¹³ = 42165546299 is a prime.

It is not a weakly prime, because it can be changed into another prime (42165554791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21082777245 + 21082777246.

It is an arithmetic number, because the mean of its divisors is an integer number (21082777246).

Almost surely, 2^42165554491 is an apocalyptic number.

42165554491 is a deficient number, since it is larger than the sum of its proper divisors (1).

42165554491 is an equidigital number, since it uses as much as digits as its factorization.

42165554491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864000, while the sum is 46.

The spelling of 42165554491 in words is "forty-two billion, one hundred sixty-five million, five hundred fifty-four thousand, four hundred ninety-one".