400001123 has 4 divisors (see below), whose sum is σ = 407548368. Its totient is φ = 392453880.

The previous prime is 400001113. The next prime is 400001137. The reversal of 400001123 is 321100004.

It is a happy number.

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 400001123 - 2⁶ = 400001059 is a prime.

It is a super-2 number, since 2×400001123² = 320001796802522258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400001113) 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, 3773543 + ... + 3773648.

It is an arithmetic number, because the mean of its divisors is an integer number (101887092).

Almost surely, 2^400001123 is an apocalyptic number.

400001123 is a deficient number, since it is larger than the sum of its proper divisors (7547245).

400001123 is an equidigital number, since it uses as much as digits as its factorization.

400001123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7547244.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 400001123 is about 20000.0280749803. The cubic root of 400001123 is about 736.8069892553.

Adding to 400001123 its reverse (321100004), we get a palindrome (721101127).

The spelling of 400001123 in words is "four hundred million, one thousand, one hundred twenty-three".