400123321 has 4 divisors (see below), whose sum is σ = 430902052. Its totient is φ = 369344592.

The previous prime is 400123307. The next prime is 400123331. The reversal of 400123321 is 123321004.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 157854096 + 242269225 = 12564^2 + 15565^2 .

It is a cyclic number.

It is not a de Polignac number, because 400123321 - 2⁵ = 400123289 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 400123295 and 400123304.

It is not an unprimeable number, because it can be changed into a prime (400123331) 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, 15389346 + ... + 15389371.

It is an arithmetic number, because the mean of its divisors is an integer number (107725513).

Almost surely, 2^400123321 is an apocalyptic number.

It is an amenable number.

400123321 is a deficient number, since it is larger than the sum of its proper divisors (30778731).

400123321 is a wasteful number, since it uses less digits than its factorization.

400123321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30778730.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 400123321 is about 20003.0827874105. The cubic root of 400123321 is about 736.8820116893.

Adding to 400123321 its reverse (123321004), we get a palindrome (523444325).

The spelling of 400123321 in words is "four hundred million, one hundred twenty-three thousand, three hundred twenty-one".