400640460 has 192 divisors, whose sum is σ = 1319915520. Its totient is φ = 89752320.

The previous prime is 400640453. The next prime is 400640467. The reversal of 400640460 is 64046004.

It is an interprime number because it is at equal distance from previous prime (400640453) and next prime (400640467).

It is a self number, because there is not a number n which added to its sum of digits gives 400640460.

It is not an unprimeable number, because it can be changed into a prime (400640467) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 538849 + ... + 539591.

It is an arithmetic number, because the mean of its divisors is an integer number (6874560).

Almost surely, 2^400640460 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 400640460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (659957760).

400640460 is an abundant number, since it is smaller than the sum of its proper divisors (919275060).

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

400640460 is a wasteful number, since it uses less digits than its factorization.

400640460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 828 (or 826 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 400640460 is about 20016.0050959226. The cubic root of 400640460 is about 737.1993358350.

Adding to 400640460 its reverse (64046004), we get a palindrome (464686464).

The spelling of 400640460 in words is "four hundred million, six hundred forty thousand, four hundred sixty".