985700021 has 2 divisors, whose sum is σ = 985700022. Its totient is φ = 985700020.

The previous prime is 985700011. The next prime is 985700033. The reversal of 985700021 is 120007589.

985700021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 590247025 + 395452996 = 24295^2 + 19886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-985700021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (985700011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 492850010 + 492850011.

It is an arithmetic number, because the mean of its divisors is an integer number (492850011).

Almost surely, 2^985700021 is an apocalyptic number.

It is an amenable number.

985700021 is a deficient number, since it is larger than the sum of its proper divisors (1).

985700021 is an equidigital number, since it uses as much as digits as its factorization.

985700021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 985700021 is about 31395.8599340741. The cubic root of 985700021 is about 995.2104370441.

The spelling of 985700021 in words is "nine hundred eighty-five million, seven hundred thousand, twenty-one".