9990388211 has 2 divisors, whose sum is σ = 9990388212. Its totient is φ = 9990388210.

The previous prime is 9990388183. The next prime is 9990388231. The reversal of 9990388211 is 1128830999.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9990388211 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9990388211.

It is not a weakly prime, because it can be changed into another prime (9990388231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995194105 + 4995194106.

It is an arithmetic number, because the mean of its divisors is an integer number (4995194106).

Almost surely, 2^9990388211 is an apocalyptic number.

9990388211 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990388211 is an equidigital number, since it uses as much as digits as its factorization.

9990388211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 279936, while the sum is 50.

The square root of 9990388211 is about 99951.9295011357. The cubic root of 9990388211 is about 2153.7442030356.

The spelling of 9990388211 in words is "nine billion, nine hundred ninety million, three hundred eighty-eight thousand, two hundred eleven".