400440402 has 32 divisors (see below), whose sum is σ = 892156800. Its totient is φ = 133136784.

The previous prime is 400440401. The next prime is 400440421. The reversal of 400440402 is 204044004.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (400440401) 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 15 ways as a sum of consecutive naturals, for example, 12099 + ... + 30777.

It is an arithmetic number, because the mean of its divisors is an integer number (27879900).

Almost surely, 2^400440402 is an apocalyptic number.

400440402 is an abundant number, since it is smaller than the sum of its proper divisors (491716398).

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

400440402 is a wasteful number, since it uses less digits than its factorization.

400440402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19087 (or 19081 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 400440402 is about 20011.0070211371. The cubic root of 400440402 is about 737.0766096881.

Adding to 400440402 its reverse (204044004), we get a palindrome (604484406).

The spelling of 400440402 in words is "four hundred million, four hundred forty thousand, four hundred two".