99869989 has 2 divisors, whose sum is σ = 99869990. Its totient is φ = 99869988.

The previous prime is 99869981. The next prime is 99870011. The reversal of 99869989 is 98996899.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97121025 + 2748964 = 9855^2 + 1658^2 .

It is a cyclic number.

It is not a de Polignac number, because 99869989 - 2³ = 99869981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99869981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49934994 + 49934995.

It is an arithmetic number, because the mean of its divisors is an integer number (49934995).

Almost surely, 2^99869989 is an apocalyptic number.

It is an amenable number.

99869989 is a deficient number, since it is larger than the sum of its proper divisors (1).

99869989 is an equidigital number, since it uses as much as digits as its factorization.

99869989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22674816, while the sum is 67.

The square root of 99869989 is about 9993.4973357679. The cubic root of 99869989 is about 463.9576435895.

The spelling of 99869989 in words is "ninety-nine million, eight hundred sixty-nine thousand, nine hundred eighty-nine".