1687980 has 48 divisors (see below), whose sum is σ = 5402880. Its totient is φ = 385728.

The previous prime is 1687969. The next prime is 1687991. The reversal of 1687980 is 897861.

It is an interprime number because it is at equal distance from previous prime (1687969) and next prime (1687991).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1590 + ... + 2429.

It is an arithmetic number, because the mean of its divisors is an integer number (112560).

2^1687980 is an apocalyptic number.

1687980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1687980 is an abundant number, since it is smaller than the sum of its proper divisors (3714900).

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

1687980 is a wasteful number, since it uses less digits than its factorization.

1687980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4038 (or 4036 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 39.

The square root of 1687980 is about 1299.2228446267. Note that the first 3 decimals coincide. The cubic root of 1687980 is about 119.0663660128.

The spelling of 1687980 in words is "one million, six hundred eighty-seven thousand, nine hundred eighty".