2043991861 has 8 divisors (see below), whose sum is σ = 2153156000. Its totient is φ = 1934986320.

The previous prime is 2043991849. The next prime is 2043991879. The reversal of 2043991861 is 1681993402.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2043991861 - 2¹¹ = 2043989813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2043991841) 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 7 ways as a sum of consecutive naturals, for example, 12711 + ... + 65188.

It is an arithmetic number, because the mean of its divisors is an integer number (269144500).

Almost surely, 2^2043991861 is an apocalyptic number.

It is an amenable number.

2043991861 is a deficient number, since it is larger than the sum of its proper divisors (109164139).

2043991861 is a wasteful number, since it uses less digits than its factorization.

2043991861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79299.

The product of its (nonzero) digits is 93312, while the sum is 43.

The square root of 2043991861 is about 45210.5282096991. The cubic root of 2043991861 is about 1269.0918468766.

The spelling of 2043991861 in words is "two billion, forty-three million, nine hundred ninety-one thousand, eight hundred sixty-one".