1021019985 has 20 divisors (see below), whose sum is σ = 1830273588. Its totient is φ = 544543776.

The previous prime is 1021019977. The next prime is 1021020019. The reversal of 1021019985 is 5899101201.

It can be written as a sum of positive squares in 2 ways, for example, as 132503121 + 888516864 = 11511^2 + 29808^2 .

It is not a de Polignac number, because 1021019985 - 2³ = 1021019977 is a prime.

It is a Curzon number.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 1260114 + ... + 1260923.

Almost surely, 2^1021019985 is an apocalyptic number.

1021019985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1021019985 is a deficient number, since it is larger than the sum of its proper divisors (809253603).

1021019985 is an equidigital number, since it uses as much as digits as its factorization.

1021019985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2521054 (or 2521045 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 36.

The square root of 1021019985 is about 31953.4033398635. The cubic root of 1021019985 is about 1006.9581337473.

The spelling of 1021019985 in words is "one billion, twenty-one million, nineteen thousand, nine hundred eighty-five".