1985220000 has 360 divisors, whose sum is σ = 7253506260. Its totient is φ = 514560000.

The previous prime is 1985219987. The next prime is 1985220037. The reversal of 1985220000 is 225891.

It can be written as a sum of positive squares in 10 ways, for example, as 1078728336 + 906491664 = 32844^2 + 30108^2 .

It is a tau number, because it is divible by the number of its divisors (360).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 7379866 + ... + 7380134.

Almost surely, 2^1985220000 is an apocalyptic number.

1985220000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1985220000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3626753130).

1985220000 is an abundant number, since it is smaller than the sum of its proper divisors (5268286260).

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

1985220000 is a wasteful number, since it uses less digits than its factorization.

1985220000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346 (or 320 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1985220000 is about 44555.8077022513. The cubic root of 1985220000 is about 1256.8097676170.

Adding to 1985220000 its reverse (225891), we get a palindrome (1985445891).

The spelling of 1985220000 in words is "one billion, nine hundred eighty-five million, two hundred twenty thousand".