400340023 has 2 divisors, whose sum is σ = 400340024. Its totient is φ = 400340022.

The previous prime is 400340009. The next prime is 400340027. The reversal of 400340023 is 320043004.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400340023 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 400339979 and 400340006.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400340027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200170011 + 200170012.

It is an arithmetic number, because the mean of its divisors is an integer number (200170012).

Almost surely, 2^400340023 is an apocalyptic number.

400340023 is a deficient number, since it is larger than the sum of its proper divisors (1).

400340023 is an equidigital number, since it uses as much as digits as its factorization.

400340023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 16.

The square root of 400340023 is about 20008.4987692730. The cubic root of 400340023 is about 737.0150165059.

Adding to 400340023 its reverse (320043004), we get a palindrome (720383027).

The spelling of 400340023 in words is "four hundred million, three hundred forty thousand, twenty-three".