2551540440 has 32 divisors (see below), whose sum is σ = 7654621680. Its totient is φ = 680410752.

The previous prime is 2551540429. The next prime is 2551540447. The reversal of 2551540440 is 440451552.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 2551540398 and 2551540407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2551540447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10631299 + ... + 10631538.

Almost surely, 2^2551540440 is an apocalyptic number.

2551540440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2551540440 is an abundant number, since it is smaller than the sum of its proper divisors (5103081240).

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

2551540440 is a wasteful number, since it uses less digits than its factorization.

2551540440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21262851 (or 21262847 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 30.

The square root of 2551540440 is about 50512.7750178111. The cubic root of 2551540440 is about 1366.4722565686.

Adding to 2551540440 its reverse (440451552), we get a palindrome (2991991992).

The spelling of 2551540440 in words is "two billion, five hundred fifty-one million, five hundred forty thousand, four hundred forty".