2581161436 has 30 divisors (see below), whose sum is σ = 5269577320. Its totient is φ = 1106207928.

The previous prime is 2581161421. The next prime is 2581161439. The reversal of 2581161436 is 6341611852.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 2581161395 and 2581161404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2581161439) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 124776 + ... + 143983.

Almost surely, 2^2581161436 is an apocalyptic number.

It is an amenable number.

2581161436 is an abundant number, since it is smaller than the sum of its proper divisors (2688415884).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2581161436 is an equidigital number, since it uses as much as digits as its factorization.

2581161436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268791 (or 268768 counting only the distinct ones).

The product of its digits is 34560, while the sum is 37.

The square root of 2581161436 is about 50805.1319848694. The cubic root of 2581161436 is about 1371.7397465542.

The spelling of 2581161436 in words is "two billion, five hundred eighty-one million, one hundred sixty-one thousand, four hundred thirty-six".