101021985 has 20 divisors (see below), whose sum is σ = 181091988. Its totient is φ = 53878176.

The previous prime is 101021981. The next prime is 101022059. The reversal of 101021985 is 589120101.

It can be written as a sum of positive squares in 2 ways, for example, as 14085009 + 86936976 = 3753^2 + 9324^2 .

It is not a de Polignac number, because 101021985 - 2² = 101021981 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (101021981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 124314 + ... + 125123.

Almost surely, 2^101021985 is an apocalyptic number.

101021985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

101021985 is a deficient number, since it is larger than the sum of its proper divisors (80070003).

101021985 is an equidigital number, since it uses as much as digits as its factorization.

101021985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249454 (or 249445 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 27.

The square root of 101021985 is about 10050.9693562362. The cubic root of 101021985 is about 465.7347385448.

The spelling of 101021985 in words is "one hundred one million, twenty-one thousand, nine hundred eighty-five".