400938945 has 24 divisors (see below), whose sum is σ = 705125568. Its totient is φ = 194393760.

The previous prime is 400938911. The next prime is 400938947. The reversal of 400938945 is 549839004.

It is not a de Polignac number, because 400938945 - 2¹⁷ = 400807873 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 400938897 and 400938906.

It is not an unprimeable number, because it can be changed into a prime (400938947) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 108637 + ... + 112266.

It is an arithmetic number, because the mean of its divisors is an integer number (29380232).

Almost surely, 2^400938945 is an apocalyptic number.

It is an amenable number.

400938945 is a deficient number, since it is larger than the sum of its proper divisors (304186623).

400938945 is a wasteful number, since it uses less digits than its factorization.

400938945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220933 (or 220922 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 42.

The square root of 400938945 is about 20023.4598658673. The cubic root of 400938945 is about 737.3823663764.

The spelling of 400938945 in words is "four hundred million, nine hundred thirty-eight thousand, nine hundred forty-five".