1985291256 has 64 divisors (see below), whose sum is σ = 5376057120. Its totient is φ = 607311360.

The previous prime is 1985291213. The next prime is 1985291257. The reversal of 1985291256 is 6521925891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985291257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35586 + ... + 72366.

Almost surely, 2^1985291256 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1985291256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2688028560).

1985291256 is an abundant number, since it is smaller than the sum of its proper divisors (3390765864).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1985291256 is a wasteful number, since it uses less digits than its factorization.

1985291256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36976 (or 36972 counting only the distinct ones).

The product of its digits is 388800, while the sum is 48.

The square root of 1985291256 is about 44556.6073214737. The cubic root of 1985291256 is about 1256.8248044333.

The spelling of 1985291256 in words is "one billion, nine hundred eighty-five million, two hundred ninety-one thousand, two hundred fifty-six".