2551656720 has 40 divisors (see below), whose sum is σ = 7910136576. Its totient is φ = 680441728.

The previous prime is 2551656697. The next prime is 2551656733. The reversal of 2551656720 is 276561552.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-3 number, since 3×2551656720³ (a number of 29 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5315712 + ... + 5316191.

Almost surely, 2^2551656720 is an apocalyptic number.

2551656720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2551656720 is an abundant number, since it is smaller than the sum of its proper divisors (5358479856).

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

2551656720 is a wasteful number, since it uses less digits than its factorization.

2551656720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10631919 (or 10631913 counting only the distinct ones).

The product of its (nonzero) digits is 126000, while the sum is 39.

The square root of 2551656720 is about 50513.9260006585. The cubic root of 2551656720 is about 1366.4930140919.

The spelling of 2551656720 in words is "two billion, five hundred fifty-one million, six hundred fifty-six thousand, seven hundred twenty".