2556403320 has 256 divisors, whose sum is σ = 8174960640. Its totient is φ = 638765568.

The previous prime is 2556403303. The next prime is 2556403391. The reversal of 2556403320 is 233046552.

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

It is a congruent number.

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, 20129097 + ... + 20129223.

It is an arithmetic number, because the mean of its divisors is an integer number (31933440).

Almost surely, 2^2556403320 is an apocalyptic number.

2556403320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2556403320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4087480320).

2556403320 is an abundant number, since it is smaller than the sum of its proper divisors (5618557320).

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

2556403320 is a wasteful number, since it uses less digits than its factorization.

2556403320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314 (or 310 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 30.

The square root of 2556403320 is about 50560.8872548732. The cubic root of 2556403320 is about 1367.3398074661.

Adding to 2556403320 its reverse (233046552), we get a palindrome (2789449872).

The spelling of 2556403320 in words is "two billion, five hundred fifty-six million, four hundred three thousand, three hundred twenty".