400442121 has 48 divisors (see below), whose sum is σ = 639999360. Its totient is φ = 240387840.

The previous prime is 400442111. The next prime is 400442131. The reversal of 400442121 is 121244004.

It is an interprime number because it is at equal distance from previous prime (400442111) and next prime (400442131).

It is not a de Polignac number, because 400442121 - 2⁶ = 400442057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 400442094 and 400442103.

It is not an unprimeable number, because it can be changed into a prime (400442111) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 245310 + ... + 246936.

It is an arithmetic number, because the mean of its divisors is an integer number (13333320).

Almost surely, 2^400442121 is an apocalyptic number.

400442121 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

400442121 is a deficient number, since it is larger than the sum of its proper divisors (239557239).

400442121 is a wasteful number, since it uses less digits than its factorization.

400442121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1726 (or 1723 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 400442121 is about 20011.0499724527. The cubic root of 400442121 is about 737.0776643876.

Adding to 400442121 its reverse (121244004), we get a palindrome (521686125).

The spelling of 400442121 in words is "four hundred million, four hundred forty-two thousand, one hundred twenty-one".