400064 has 56 divisors (see below), whose sum is σ = 975360. Its totient is φ = 158976.

The previous prime is 400051. The next prime is 400067. The reversal of 400064 is 460004.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8489 + ... + 8535.

2⁴⁰⁰⁰⁶⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (487680).

400064 is an abundant number, since it is smaller than the sum of its proper divisors (575296).

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

400064 is a wasteful number, since it uses less digits than its factorization.

400064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85 (or 75 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 400064 is about 632.5061264525. The cubic root of 400064 is about 73.6845593968.

Adding to 400064 its reverse (460004), we get a palindrome (860068).

The spelling of 400064 in words is "four hundred thousand, sixty-four".