400437020 has 12 divisors (see below), whose sum is σ = 840917784. Its totient is φ = 160174800.

The previous prime is 400436999. The next prime is 400437029. The reversal of 400437020 is 20734004.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 20021851 = 400437020 / (4 + 0 + 0 + 4 + 3 + 7 + 0 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 400436983 and 400437001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400437029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10010906 + ... + 10010945.

It is an arithmetic number, because the mean of its divisors is an integer number (70076482).

Almost surely, 2^400437020 is an apocalyptic number.

It is an amenable number.

400437020 is an abundant number, since it is smaller than the sum of its proper divisors (440480764).

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

400437020 is a wasteful number, since it uses less digits than its factorization.

400437020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20021860 (or 20021858 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 20.

The square root of 400437020 is about 20010.9225174653. The cubic root of 400437020 is about 737.0745346394.

The spelling of 400437020 in words is "four hundred million, four hundred thirty-seven thousand, twenty".