2561646234 has 128 divisors (see below), whose sum is σ = 6400051200. Its totient is φ = 667180800.

The previous prime is 2561646209. The next prime is 2561646277. The reversal of 2561646234 is 4326461652.

It is a junction number, because it is equal to n+sod(n) for n = 2561646192 and 2561646201.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2981697 + ... + 2982555.

It is an arithmetic number, because the mean of its divisors is an integer number (50000400).

Almost surely, 2^2561646234 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2561646234, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3200025600).

2561646234 is an abundant number, since it is smaller than the sum of its proper divisors (3838404966).

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

2561646234 is a wasteful number, since it uses less digits than its factorization.

2561646234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1028.

The product of its digits is 207360, while the sum is 39.

The square root of 2561646234 is about 50612.7082262943. The cubic root of 2561646234 is about 1368.2739258152.

The spelling of 2561646234 in words is "two billion, five hundred sixty-one million, six hundred forty-six thousand, two hundred thirty-four".