2991905061 has 4 divisors (see below), whose sum is σ = 3989206752. Its totient is φ = 1994603372.

The previous prime is 2991905057. The next prime is 2991905087. The reversal of 2991905061 is 1605091992.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2991905061 - 2² = 2991905057 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2991905011) 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, 498650841 + ... + 498650846.

It is an arithmetic number, because the mean of its divisors is an integer number (997301688).

Almost surely, 2^2991905061 is an apocalyptic number.

It is an amenable number.

2991905061 is a deficient number, since it is larger than the sum of its proper divisors (997301691).

2991905061 is an equidigital number, since it uses as much as digits as its factorization.

2991905061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 997301690.

The product of its (nonzero) digits is 43740, while the sum is 42.

The square root of 2991905061 is about 54698.3094894166. The cubic root of 2991905061 is about 1440.9511882042.

The spelling of 2991905061 in words is "two billion, nine hundred ninety-one million, nine hundred five thousand, sixty-one".