400075668 has 18 divisors (see below), whose sum is σ = 1011302474. Its totient is φ = 133358544.

The previous prime is 400075607. The next prime is 400075681. The reversal of 400075668 is 866570004.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 225360144 + 174715524 = 15012^2 + 13218^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 11113213 = 400075668 / (4 + 0 + 0 + 0 + 7 + 5 + 6 + 6 + 8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5556571 + ... + 5556642.

Almost surely, 2^400075668 is an apocalyptic number.

It is an amenable number.

400075668 is an abundant number, since it is smaller than the sum of its proper divisors (611226806).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400075668 is a wasteful number, since it uses less digits than its factorization.

400075668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11113223 (or 11113218 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 400075668 is about 20001.8916105452. The cubic root of 400075668 is about 736.8527573480.

The spelling of 400075668 in words is "four hundred million, seventy-five thousand, six hundred sixty-eight".