1985599643 has 12 divisors (see below), whose sum is σ = 2111521440. Its totient is φ = 1866805632.

The previous prime is 1985599573. The next prime is 1985599673. The reversal of 1985599643 is 3469955891.

It is not a de Polignac number, because 1985599643 - 2⁸ = 1985599387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1985599673) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 315653 + ... + 321881.

It is an arithmetic number, because the mean of its divisors is an integer number (175960120).

Almost surely, 2^1985599643 is an apocalyptic number.

1985599643 is a deficient number, since it is larger than the sum of its proper divisors (125921797).

1985599643 is a wasteful number, since it uses less digits than its factorization.

1985599643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7366 (or 7349 counting only the distinct ones).

The product of its digits is 10497600, while the sum is 59.

The square root of 1985599643 is about 44560.0678073990. The cubic root of 1985599643 is about 1256.8898777339.

The spelling of 1985599643 in words is "one billion, nine hundred eighty-five million, five hundred ninety-nine thousand, six hundred forty-three".