1021109985 has 48 divisors (see below), whose sum is σ = 2037409920. Its totient is φ = 463415040.

The previous prime is 1021109983. The next prime is 1021109987. The reversal of 1021109985 is 5899011201.

It is an interprime number because it is at equal distance from previous prime (1021109983) and next prime (1021109987).

It is not a de Polignac number, because 1021109985 - 2¹ = 1021109983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1021109983) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 32125 + ... + 55445.

It is an arithmetic number, because the mean of its divisors is an integer number (42446040).

Almost surely, 2^1021109985 is an apocalyptic number.

1021109985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1021109985 is a deficient number, since it is larger than the sum of its proper divisors (1016299935).

1021109985 is a wasteful number, since it uses less digits than its factorization.

1021109985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23478 (or 23475 counting only the distinct ones).

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

The square root of 1021109985 is about 31954.8116095213. The cubic root of 1021109985 is about 1006.9877197073.

The spelling of 1021109985 in words is "one billion, twenty-one million, one hundred nine thousand, nine hundred eighty-five".