1980645 has 16 divisors (see below), whose sum is σ = 3307392. Its totient is φ = 1010240.

The previous prime is 1980637. The next prime is 1980659. The reversal of 1980645 is 5460891.

It is not a de Polignac number, because 1980645 - 2³ = 1980637 is a prime.

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, 2526 + ... + 3215.

It is an arithmetic number, because the mean of its divisors is an integer number (206712).

2^1980645 is an apocalyptic number.

1980645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1980645 is a deficient number, since it is larger than the sum of its proper divisors (1326747).

1980645 is a wasteful number, since it uses less digits than its factorization.

1980645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5772.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 1980645 is about 1407.3539000550. The cubic root of 1980645 is about 125.5843572889.

The spelling of 1980645 in words is "one million, nine hundred eighty thousand, six hundred forty-five".