400439121 has 16 divisors (see below), whose sum is σ = 554350080. Its totient is φ = 256844160.

The previous prime is 400439119. The next prime is 400439129. The reversal of 400439121 is 121934004.

It is not a de Polignac number, because 400439121 - 2¹ = 400439119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 400439091 and 400439100.

It is not an unprimeable number, because it can be changed into a prime (400439129) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3645 + ... + 28533.

It is an arithmetic number, because the mean of its divisors is an integer number (34646880).

Almost surely, 2^400439121 is an apocalyptic number.

It is an amenable number.

400439121 is a deficient number, since it is larger than the sum of its proper divisors (153910959).

400439121 is a wasteful number, since it uses less digits than its factorization.

400439121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25096.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 400439121 is about 20010.9750137268. The cubic root of 400439121 is about 737.0758237234.

The spelling of 400439121 in words is "four hundred million, four hundred thirty-nine thousand, one hundred twenty-one".