400404442420 has 48 divisors (see below), whose sum is σ = 853485949008. Its totient is φ = 157770905600.

The previous prime is 400404442409. The next prime is 400404442439. The reversal of 400404442420 is 24244404004.

It can be written as a sum of positive squares in 8 ways, for example, as 154749397924 + 245655044496 = 393382^2 + 495636^2 .

It is a congruent number.

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, 105157 + ... + 901036.

It is an arithmetic number, because the mean of its divisors is an integer number (17780957271).

Almost surely, 2^400404442420 is an apocalyptic number.

It is an amenable number.

400404442420 is an abundant number, since it is smaller than the sum of its proper divisors (453081506588).

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

400404442420 is a wasteful number, since it uses less digits than its factorization.

400404442420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1006500 (or 1006498 counting only the distinct ones).

The product of its (nonzero) digits is 16384, while the sum is 28.

Adding to 400404442420 its reverse (24244404004), we get a palindrome (424648846424).

The spelling of 400404442420 in words is "four hundred billion, four hundred four million, four hundred forty-two thousand, four hundred twenty".