1985511983 has 16 divisors (see below), whose sum is σ = 2444904000. Its totient is φ = 1570185216.

The previous prime is 1985511967. The next prime is 1985512003. The reversal of 1985511983 is 3891155891.

It is a cyclic number.

It is not a de Polignac number, because 1985511983 - 2⁴ = 1985511967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985511083) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 246191 + ... + 254127.

It is an arithmetic number, because the mean of its divisors is an integer number (152806500).

Almost surely, 2^1985511983 is an apocalyptic number.

1985511983 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1985511983 is a deficient number, since it is larger than the sum of its proper divisors (459392017).

1985511983 is a wasteful number, since it uses less digits than its factorization.

1985511983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10706.

The product of its digits is 388800, while the sum is 50.

The square root of 1985511983 is about 44559.0841804452. The cubic root of 1985511983 is about 1256.8713811237.

The spelling of 1985511983 in words is "one billion, nine hundred eighty-five million, five hundred eleven thousand, nine hundred eighty-three".