3561799991 has 4 divisors (see below), whose sum is σ = 3579880392. Its totient is φ = 3543719592.

The previous prime is 3561799979. The next prime is 3561800027. The reversal of 3561799991 is 1999971653.

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

It is a cyclic number.

It is not a de Polignac number, because 3561799991 - 2²² = 3557605687 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3561799991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3561799921) 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, 9039905 + ... + 9040298.

It is an arithmetic number, because the mean of its divisors is an integer number (894970098).

Almost surely, 2^3561799991 is an apocalyptic number.

3561799991 is a deficient number, since it is larger than the sum of its proper divisors (18080401).

3561799991 is a wasteful number, since it uses less digits than its factorization.

3561799991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18080400.

The product of its digits is 4133430, while the sum is 59.

The square root of 3561799991 is about 59680.8176133672. The cubic root of 3561799991 is about 1527.1786459454.

The spelling of 3561799991 in words is "three billion, five hundred sixty-one million, seven hundred ninety-nine thousand, nine hundred ninety-one".