9990251 has 2 divisors, whose sum is σ = 9990252. Its totient is φ = 9990250.

The previous prime is 9990221. The next prime is 9990263. The reversal of 9990251 is 1520999.

9990251 is nontrivially palindromic in base 5.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9990251 - 2⁶ = 9990187 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (9990221) 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 as a sum of consecutive naturals, namely, 4995125 + 4995126.

It is an arithmetic number, because the mean of its divisors is an integer number (4995126).

Almost surely, 2^9990251 is an apocalyptic number.

9990251 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990251 is an equidigital number, since it uses as much as digits as its factorization.

9990251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7290, while the sum is 35.

The square root of 9990251 is about 3160.7358320492. The cubic root of 9990251 is about 215.3734342933.

The spelling of 9990251 in words is "nine million, nine hundred ninety thousand, two hundred fifty-one".