2581249636 has 81 divisors (see below), whose sum is σ = 5574992787. Its totient is φ = 1042539120.

The previous prime is 2581249633. The next prime is 2581249639. The reversal of 2581249636 is 6369421852.

The square root of 2581249636 is 50806.

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

It is an interprime number because it is at equal distance from previous prime (2581249633) and next prime (2581249639).

It is not an unprimeable number, because it can be changed into a prime (2581249633) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 13514301 + ... + 13514491.

Almost surely, 2^2581249636 is an apocalyptic number.

2581249636 is the 50806-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2581249636

2581249636 is an abundant number, since it is smaller than the sum of its proper divisors (2993743151).

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

2581249636 is a wasteful number, since it uses less digits than its factorization.

2581249636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438 (or 219 counting only the distinct ones).

The product of its digits is 622080, while the sum is 46.

The cubic root of 2581249636 is about 1371.7553707956.

The spelling of 2581249636 in words is "two billion, five hundred eighty-one million, two hundred forty-nine thousand, six hundred thirty-six".