400064789 has 2 divisors, whose sum is σ = 400064790. Its totient is φ = 400064788.

The previous prime is 400064759. The next prime is 400064801. The reversal of 400064789 is 987460004.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 340697764 + 59367025 = 18458^2 + 7705^2 .

It is a cyclic number.

It is not a de Polignac number, because 400064789 - 2¹² = 400060693 is a prime.

It is a super-2 number, since 2×400064789² = 320103670795229042, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400064759) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200032394 + 200032395.

It is an arithmetic number, because the mean of its divisors is an integer number (200032395).

Almost surely, 2^400064789 is an apocalyptic number.

It is an amenable number.

400064789 is a deficient number, since it is larger than the sum of its proper divisors (1).

400064789 is an equidigital number, since it uses as much as digits as its factorization.

400064789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 400064789 is about 20001.6196594176. The cubic root of 400064789 is about 736.8460783666.

The spelling of 400064789 in words is "four hundred million, sixty-four thousand, seven hundred eighty-nine".