42891220829 has 4 divisors (see below), whose sum is σ = 42907587900. Its totient is φ = 42874853760.

The previous prime is 42891220789. The next prime is 42891220831. The reversal of 42891220829 is 92802219824.

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 39889276729 + 3001944100 = 199723^2 + 54790^2 .

It is a cyclic number.

It is not a de Polignac number, because 42891220829 - 2³² = 38596253533 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42891240829) 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, 8179604 + ... + 8184845.

It is an arithmetic number, because the mean of its divisors is an integer number (10726896975).

Almost surely, 2^42891220829 is an apocalyptic number.

It is an amenable number.

42891220829 is a deficient number, since it is larger than the sum of its proper divisors (16367071).

42891220829 is a wasteful number, since it uses less digits than its factorization.

42891220829 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16367070.

The product of its (nonzero) digits is 331776, while the sum is 47.

The spelling of 42891220829 in words is "forty-two billion, eight hundred ninety-one million, two hundred twenty thousand, eight hundred twenty-nine".