400505121 has 16 divisors (see below), whose sum is σ = 597875520. Its totient is φ = 264962880.

The previous prime is 400505111. The next prime is 400505201. The reversal of 400505121 is 121505004.

400505121 is a `hidden beast` number, since 40 + 0 + 505 + 121 = 666.

It is not a de Polignac number, because 400505121 - 2⁹ = 400504609 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 400505094 and 400505103.

It is not an unprimeable number, because it can be changed into a prime (400505111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53080 + ... + 60153.

It is an arithmetic number, because the mean of its divisors is an integer number (37367220).

Almost surely, 2^400505121 is an apocalyptic number.

It is an amenable number.

400505121 is a deficient number, since it is larger than the sum of its proper divisors (197370399).

400505121 is a wasteful number, since it uses less digits than its factorization.

400505121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113373 (or 113367 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 400505121 is about 20012.6240408398. The cubic root of 400505121 is about 737.1163162139.

It can be divided in two parts, 400 and 505121, that added together give a square (505521 = 711²).

The spelling of 400505121 in words is "four hundred million, five hundred five thousand, one hundred twenty-one".