981699989 has 2 divisors, whose sum is σ = 981699990. Its totient is φ = 981699988.

The previous prime is 981699931. The next prime is 981700001. The reversal of 981699989 is 989996189.

981699989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 887027089 + 94672900 = 29783^2 + 9730^2 .

It is a cyclic number.

It is not a de Polignac number, because 981699989 - 2²⁴ = 964922773 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (981699919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 490849994 + 490849995.

It is an arithmetic number, because the mean of its divisors is an integer number (490849995).

Almost surely, 2^981699989 is an apocalyptic number.

It is an amenable number.

981699989 is a deficient number, since it is larger than the sum of its proper divisors (1).

981699989 is an equidigital number, since it uses as much as digits as its factorization.

981699989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22674816, while the sum is 68.

The square root of 981699989 is about 31332.0919984606. The cubic root of 981699989 is about 993.8624033081.

The spelling of 981699989 in words is "nine hundred eighty-one million, six hundred ninety-nine thousand, nine hundred eighty-nine".