1985780872 has 16 divisors (see below), whose sum is σ = 3732630300. Its totient is φ = 990412800.

The previous prime is 1985780869. The next prime is 1985780873. The reversal of 1985780872 is 2780875891.

It can be written as a sum of positive squares in 2 ways, for example, as 1344982276 + 640798596 = 36674^2 + 25314^2 .

It is not an unprimeable number, because it can be changed into a prime (1985780873) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 306297 + ... + 312712.

Almost surely, 2^1985780872 is an apocalyptic number.

It is an amenable number.

1985780872 is a deficient number, since it is larger than the sum of its proper divisors (1746849428).

1985780872 is a wasteful number, since it uses less digits than its factorization.

1985780872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619416 (or 619412 counting only the distinct ones).

The product of its (nonzero) digits is 2257920, while the sum is 55.

The square root of 1985780872 is about 44562.1012969541. The cubic root of 1985780872 is about 1256.9281160509.

The spelling of 1985780872 in words is "one billion, nine hundred eighty-five million, seven hundred eighty thousand, eight hundred seventy-two".