2991761809 has 9 divisors (see below), whose sum is σ = 3032843593. Its totient is φ = 2951231332.

The previous prime is 2991761807. The next prime is 2991761827. The reversal of 2991761809 is 9081671992.

The square root of 2991761809 is 54697.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 2991761809 - 2¹ = 2991761807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2991761803) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4539522 + ... + 4540180.

Almost surely, 2^2991761809 is an apocalyptic number.

2991761809 is the 54697-th square number.

2991761809 is the 27349-th centered octagonal number.

It is an amenable number.

2991761809 is a deficient number, since it is larger than the sum of its proper divisors (41081784).

2991761809 is an frugal number, since it uses more digits than its factorization.

2991761809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1484 (or 742 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 52.

The cubic root of 2991761809 is about 1440.9281903227.

The spelling of 2991761809 in words is "two billion, nine hundred ninety-one million, seven hundred sixty-one thousand, eight hundred nine".