400031442020 has 36 divisors (see below), whose sum is σ = 977219667900. Its totient is φ = 137153636928.

The previous prime is 400031442017. The next prime is 400031442101. The reversal of 400031442020 is 20244130004.

It can be written as a sum of positive squares in 2 ways, for example, as 209286120484 + 190745321536 = 457478^2 + 436744^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 400031441983 and 400031442001.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 204096695 + ... + 204098654.

It is an arithmetic number, because the mean of its divisors is an integer number (27144990775).

Almost surely, 2^400031442020 is an apocalyptic number.

It is an amenable number.

400031442020 is an abundant number, since it is smaller than the sum of its proper divisors (577188225880).

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

400031442020 is a wasteful number, since it uses less digits than its factorization.

400031442020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408195372 (or 408195363 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 400031442020 its reverse (20244130004), we get a palindrome (420275572024).

The spelling of 400031442020 in words is "four hundred billion, thirty-one million, four hundred forty-two thousand, twenty".