402400040 has 64 divisors (see below), whose sum is σ = 1036713600. Its totient is φ = 137703168.

The previous prime is 402400039. The next prime is 402400067. The reversal of 402400040 is 40004204.

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

It is a junction number, because it is equal to n+sod(n) for n = 402399988 and 402400024.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 197507 + ... + 199533.

It is an arithmetic number, because the mean of its divisors is an integer number (16198650).

Almost surely, 2^402400040 is an apocalyptic number.

402400040 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 402400040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (518356800).

402400040 is an abundant number, since it is smaller than the sum of its proper divisors (634313560).

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

402400040 is a wasteful number, since it uses less digits than its factorization.

402400040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2754 (or 2750 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 14.

The square root of 402400040 is about 20059.9112660051. The cubic root of 402400040 is about 738.2769993498.

Adding to 402400040 its reverse (40004204), we get a palindrome (442404244).

The spelling of 402400040 in words is "four hundred two million, four hundred thousand, forty".