400021704 has 48 divisors (see below), whose sum is σ = 1130500800. Its totient is φ = 127542624.

The previous prime is 400021693. The next prime is 400021717. The reversal of 400021704 is 407120004.

It is a happy number.

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

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 119124 + ... + 122435.

It is an arithmetic number, because the mean of its divisors is an integer number (23552100).

Almost surely, 2^400021704 is an apocalyptic number.

It is an amenable number.

400021704 is an abundant number, since it is smaller than the sum of its proper divisors (730479096).

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

400021704 is a wasteful number, since it uses less digits than its factorization.

400021704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241594 (or 241587 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 400021704 is about 20000.5425926398. The cubic root of 400021704 is about 736.8196258570.

Adding to 400021704 its reverse (407120004), we get a palindrome (807141708).

The spelling of 400021704 in words is "four hundred million, twenty-one thousand, seven hundred four".