2891236481 has 4 divisors (see below), whose sum is σ = 3304270272. Its totient is φ = 2478202692.

The previous prime is 2891236477. The next prime is 2891236487. The reversal of 2891236481 is 1846321982.

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 not a de Polignac number, because 2891236481 - 2² = 2891236477 is a prime.

It is a super-2 number, since 2×2891236481² = 16718496778130526722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2891236487) 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, 206516885 + ... + 206516898.

It is an arithmetic number, because the mean of its divisors is an integer number (826067568).

Almost surely, 2^2891236481 is an apocalyptic number.

It is an amenable number.

2891236481 is a deficient number, since it is larger than the sum of its proper divisors (413033791).

2891236481 is an equidigital number, since it uses as much as digits as its factorization.

2891236481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413033790.

The product of its digits is 165888, while the sum is 44.

The square root of 2891236481 is about 53770.2192761012. The cubic root of 2891236481 is about 1424.6052430286.

The spelling of 2891236481 in words is "two billion, eight hundred ninety-one million, two hundred thirty-six thousand, four hundred eighty-one".