1985984975 has 24 divisors (see below), whose sum is σ = 2791644240. Its totient is φ = 1389381120.

The previous prime is 1985984969. The next prime is 1985984983. The reversal of 1985984975 is 5794895891.

It is a happy number.

It is not a de Polignac number, because 1985984975 - 2⁶ = 1985984911 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (65).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 154634 + ... + 166983.

It is an arithmetic number, because the mean of its divisors is an integer number (116318510).

Almost surely, 2^1985984975 is an apocalyptic number.

1985984975 is a deficient number, since it is larger than the sum of its proper divisors (805659265).

1985984975 is a wasteful number, since it uses less digits than its factorization.

1985984975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321659 (or 321654 counting only the distinct ones).

The product of its digits is 32659200, while the sum is 65.

The square root of 1985984975 is about 44564.3913343378. The cubic root of 1985984975 is about 1256.9711778701.

The spelling of 1985984975 in words is "one billion, nine hundred eighty-five million, nine hundred eighty-four thousand, nine hundred seventy-five".