400023123 has 4 divisors (see below), whose sum is σ = 533364168. Its totient is φ = 266682080.

The previous prime is 400023097. The next prime is 400023139. The reversal of 400023123 is 321320004.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 400023123 - 2⁸ = 400022867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (400023223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66670518 + ... + 66670523.

It is an arithmetic number, because the mean of its divisors is an integer number (133341042).

Almost surely, 2^400023123 is an apocalyptic number.

400023123 is a deficient number, since it is larger than the sum of its proper divisors (133341045).

400023123 is a wasteful number, since it uses less digits than its factorization.

400023123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133341044.

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 400023123 is about 20000.5780666460. The cubic root of 400023123 is about 736.8204970979.

Adding to 400023123 its reverse (321320004), we get a palindrome (721343127).

The spelling of 400023123 in words is "four hundred million, twenty-three thousand, one hundred twenty-three".