400218025 has 24 divisors (see below), whose sum is σ = 503807040. Its totient is φ = 315351360.

The previous prime is 400218017. The next prime is 400218031. The reversal of 400218025 is 520812004.

It is not a de Polignac number, because 400218025 - 2³ = 400218017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 400217987 and 400218005.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 618252 + ... + 618898.

It is an arithmetic number, because the mean of its divisors is an integer number (20991960).

Almost surely, 2^400218025 is an apocalyptic number.

It is an amenable number.

400218025 is a deficient number, since it is larger than the sum of its proper divisors (103589015).

400218025 is a wasteful number, since it uses less digits than its factorization.

400218025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 993 (or 988 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 400218025 is about 20005.4498824695. The cubic root of 400218025 is about 736.9401439078.

The spelling of 400218025 in words is "four hundred million, two hundred eighteen thousand, twenty-five".