998907631 has 2 divisors, whose sum is σ = 998907632.
Its totient is φ = 998907630.
The previous prime is 998907629. The next prime is 998907643. The reversal of 998907631 is 136709899.
It is a weak prime.
It is an emirp because it is prime and its reverse (136709899) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 998907631 - 21 = 998907629 is a prime.
It is a super-2 number, since 2×9989076312 = 1995632910540064322, which contains 22 as substring.
Together with 998907629, it forms a pair of twin primes.
It is the 31606-th Hogben number.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (998907601) by changing a digit.
It is a nontrivial repunit in base 31605.
It is a pernicious number, because its binary representation contains a prime number (19) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499453815 + 499453816.
It is an arithmetic number, because the mean of its divisors is an integer number (499453816).
Almost surely, 2998907631 is an apocalyptic number.
998907631 is a deficient number, since it is larger than the sum of its proper divisors (1).
998907631 is an equidigital number, since it uses as much as digits as its factorization.
998907631 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 734832, while the sum is 52.
The square root of 998907631 is about 31605.5000118650.
The cubic root of 998907631 is about 999.6357443339.
The spelling of 998907631 in words is "nine hundred ninety-eight million, nine hundred seven thousand, six hundred thirty-one".