1985947839 has 6 divisors (see below), whose sum is σ = 2868591336. Its totient is φ = 1323965220.

The previous prime is 1985947783. The next prime is 1985947853. The reversal of 1985947839 is 9387495891.

1985947839 is a `hidden beast` number, since 1 + 9 + 8 + 594 + 7 + 8 + 39 = 666.

It is not a de Polignac number, because 1985947839 - 2¹¹ = 1985945791 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985947039) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 110330427 + ... + 110330444.

It is an arithmetic number, because the mean of its divisors is an integer number (478098556).

Almost surely, 2^1985947839 is an apocalyptic number.

1985947839 is a deficient number, since it is larger than the sum of its proper divisors (882643497).

1985947839 is a wasteful number, since it uses less digits than its factorization.

1985947839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220660877 (or 220660874 counting only the distinct ones).

The product of its digits is 19595520, while the sum is 63.

The square root of 1985947839 is about 44563.9746768620. The cubic root of 1985947839 is about 1256.9633431058.

The spelling of 1985947839 in words is "one billion, nine hundred eighty-five million, nine hundred forty-seven thousand, eight hundred thirty-nine".