400013424 has 160 divisors (see below), whose sum is σ = 1211351040. Its totient is φ = 126137088.

The previous prime is 400013423. The next prime is 400013461. The reversal of 400013424 is 424310004.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 400013397 and 400013406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400013423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1261714 + ... + 1262030.

It is an arithmetic number, because the mean of its divisors is an integer number (7570944).

Almost surely, 2^400013424 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 400013424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (605675520).

400013424 is an abundant number, since it is smaller than the sum of its proper divisors (811337616).

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

400013424 is a wasteful number, since it uses less digits than its factorization.

400013424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484 (or 472 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 400013424 is about 20000.3355971844. The cubic root of 400013424 is about 736.8145420423.

Adding to 400013424 its reverse (424310004), we get a palindrome (824323428).

It can be divided in two parts, 4000 and 13424, that added together give a square (17424 = 132²).

The spelling of 400013424 in words is "four hundred million, thirteen thousand, four hundred twenty-four".