400030993 has 2 divisors, whose sum is σ = 400030994. Its totient is φ = 400030992.

The previous prime is 400030987. The next prime is 400031041. The reversal of 400030993 is 399030004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 383846464 + 16184529 = 19592^2 + 4023^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400030993 is a prime.

It is a super-3 number, since 3×400030993³ (a number of 27 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (400030963) by changing a digit.

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, 200015496 + 200015497.

It is an arithmetic number, because the mean of its divisors is an integer number (200015497).

Almost surely, 2^400030993 is an apocalyptic number.

It is an amenable number.

400030993 is a deficient number, since it is larger than the sum of its proper divisors (1).

400030993 is an equidigital number, since it uses as much as digits as its factorization.

400030993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 28.

The square root of 400030993 is about 20000.7748099917. The cubic root of 400030993 is about 736.8253291013.

Adding to 400030993 its reverse (399030004), we get a palindrome (799060997).

The spelling of 400030993 in words is "four hundred million, thirty thousand, nine hundred ninety-three".