4109778661 has 4 divisors (see below), whose sum is σ = 4111725772. Its totient is φ = 4107831552.

The previous prime is 4109778583. The next prime is 4109778671. The reversal of 4109778661 is 1668779014.

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 1420837636 + 2688941025 = 37694^2 + 51855^2 .

It is a cyclic number.

It is not a de Polignac number, because 4109778661 - 2⁹ = 4109778149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4109778671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 970386 + ... + 974611.

It is an arithmetic number, because the mean of its divisors is an integer number (1027931443).

Almost surely, 2^4109778661 is an apocalyptic number.

It is an amenable number.

4109778661 is a deficient number, since it is larger than the sum of its proper divisors (1947111).

4109778661 is a wasteful number, since it uses less digits than its factorization.

4109778661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1947110.

The product of its (nonzero) digits is 508032, while the sum is 49.

The square root of 4109778661 is about 64107.5554127593. Note that the first 3 decimals coincide. The cubic root of 4109778661 is about 1601.7920884967.

The spelling of 4109778661 in words is "four billion, one hundred nine million, seven hundred seventy-eight thousand, six hundred sixty-one".