2581643426 has 32 divisors (see below), whose sum is σ = 4178126448. Its totient is φ = 1192038400.

The previous prime is 2581643387. The next prime is 2581643429. The reversal of 2581643426 is 6243461852.

It can be written as a sum of positive squares in 8 ways, for example, as 788205625 + 1793437801 = 28075^2 + 42349^2 .

It is not an unprimeable number, because it can be changed into a prime (2581643429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 384716 + ... + 391368.

Almost surely, 2^2581643426 is an apocalyptic number.

2581643426 is a deficient number, since it is larger than the sum of its proper divisors (1596483022).

2581643426 is a wasteful number, since it uses less digits than its factorization.

2581643426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6886.

The product of its digits is 276480, while the sum is 41.

The square root of 2581643426 is about 50809.8752803035. The cubic root of 2581643426 is about 1371.8251246172.

The spelling of 2581643426 in words is "two billion, five hundred eighty-one million, six hundred forty-three thousand, four hundred twenty-six".