400390093 has 2 divisors, whose sum is σ = 400390094. Its totient is φ = 400390092.

The previous prime is 400390043. The next prime is 400390099. The reversal of 400390093 is 390093004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 397523844 + 2866249 = 19938^2 + 1693^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400390093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400390099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200195046 + 200195047.

It is an arithmetic number, because the mean of its divisors is an integer number (200195047).

Almost surely, 2^400390093 is an apocalyptic number.

It is an amenable number.

400390093 is a deficient number, since it is larger than the sum of its proper divisors (1).

400390093 is an equidigital number, since it uses as much as digits as its factorization.

400390093 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 400390093 is about 20009.7499484626. The cubic root of 400390093 is about 737.0457410578.

The spelling of 400390093 in words is "four hundred million, three hundred ninety thousand, ninety-three".