990000731 has 2 divisors, whose sum is σ = 990000732. Its totient is φ = 990000730.

The previous prime is 990000689. The next prime is 990000733. The reversal of 990000731 is 137000099.

990000731 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 is a cyclic number.

It is not a de Polignac number, because 990000731 - 2¹⁸ = 989738587 is a prime.

It is a super-2 number, since 2×990000731² = 1960202894761068722, which contains 22 as substring.

Together with 990000733, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 990000694 and 990000703.

It is not a weakly prime, because it can be changed into another prime (990000733) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495000365 + 495000366.

It is an arithmetic number, because the mean of its divisors is an integer number (495000366).

Almost surely, 2^990000731 is an apocalyptic number.

990000731 is a deficient number, since it is larger than the sum of its proper divisors (1).

990000731 is an equidigital number, since it uses as much as digits as its factorization.

990000731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1701, while the sum is 29.

The square root of 990000731 is about 31464.2770614549. The cubic root of 990000731 is about 996.6557387173.

The spelling of 990000731 in words is "nine hundred ninety million, seven hundred thirty-one", and thus it is an aban number.