2521661680 has 40 divisors (see below), whose sum is σ = 6207741072. Its totient is φ = 949330944.

The previous prime is 2521661669. The next prime is 2521661717. The reversal of 2521661680 is 861661252.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 925722 + ... + 928441.

Almost surely, 2^2521661680 is an apocalyptic number.

2521661680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2521661680 is an abundant number, since it is smaller than the sum of its proper divisors (3686079392).

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

2521661680 is a wasteful number, since it uses less digits than its factorization.

2521661680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1854193 (or 1854187 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 2521661680 is about 50216.1495935322. The cubic root of 2521661680 is about 1361.1174639209.

The spelling of 2521661680 in words is "two billion, five hundred twenty-one million, six hundred sixty-one thousand, six hundred eighty".