42126666881 has 4 divisors (see below), whose sum is σ = 45367179732. Its totient is φ = 38886154032.

The previous prime is 42126666823. The next prime is 42126666887. The reversal of 42126666881 is 18866662124.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11437233025 + 30689433856 = 106945^2 + 175184^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42126666881 is a prime.

It is a super-2 number, since 2×42126666881² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42126666887) 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 in 3 ways as a sum of consecutive naturals, for example, 1620256406 + ... + 1620256431.

It is an arithmetic number, because the mean of its divisors is an integer number (11341794933).

Almost surely, 2^42126666881 is an apocalyptic number.

It is an amenable number.

42126666881 is a deficient number, since it is larger than the sum of its proper divisors (3240512851).

42126666881 is a wasteful number, since it uses less digits than its factorization.

42126666881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3240512850.

The product of its digits is 1327104, while the sum is 50.

The spelling of 42126666881 in words is "forty-two billion, one hundred twenty-six million, six hundred sixty-six thousand, eight hundred eighty-one".