2156680 has 16 divisors (see below), whose sum is σ = 4852620. Its totient is φ = 862656.

The previous prime is 2156669. The next prime is 2156681. The reversal of 2156680 is 866512.

It can be written as a sum of positive squares in 2 ways, for example, as 1943236 + 213444 = 1394^2 + 462^2 .

It is not an unprimeable number, because it can be changed into a prime (2156681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26919 + ... + 26998.

2^2156680 is an apocalyptic number.

2156680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2156680 is an abundant number, since it is smaller than the sum of its proper divisors (2695940).

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

2156680 is a wasteful number, since it uses less digits than its factorization.

2156680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53928 (or 53924 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 2156680 is about 1468.5639243833. The cubic root of 2156680 is about 129.1998185226.

The spelling of 2156680 in words is "two million, one hundred fifty-six thousand, six hundred eighty".