400018432 has 88 divisors (see below), whose sum is σ = 924097680. Its totient is φ = 171048960.

The previous prime is 400018429. The next prime is 400018439. The reversal of 400018432 is 234810004.

It is a tau number, because it is divible by the number of its divisors (88).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (400018439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 190444 + ... + 192532.

It is an arithmetic number, because the mean of its divisors is an integer number (10501110).

Almost surely, 2^400018432 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 400018432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (462048840).

400018432 is an abundant number, since it is smaller than the sum of its proper divisors (524079248).

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

400018432 is a wasteful number, since it uses less digits than its factorization.

400018432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2137 (or 2119 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 400018432 is about 20000.4607946917. The cubic root of 400018432 is about 736.8176168990.

Adding to 400018432 its reverse (234810004), we get a palindrome (634828436).

The spelling of 400018432 in words is "four hundred million, eighteen thousand, four hundred thirty-two".