406426820 has 48 divisors (see below), whose sum is σ = 906011568. Its totient is φ = 152616960.

The previous prime is 406426819. The next prime is 406426849. The reversal of 406426820 is 28624604.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 565504 + 405861316 = 752^2 + 20146^2 .

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, 155444 + ... + 158036.

It is an arithmetic number, because the mean of its divisors is an integer number (18875241).

Almost surely, 2^406426820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 406426820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (453005784).

406426820 is an abundant number, since it is smaller than the sum of its proper divisors (499584748).

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

406426820 is a wasteful number, since it uses less digits than its factorization.

406426820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3080 (or 3078 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 406426820 is about 20160.0302579138. The cubic root of 406426820 is about 740.7314535274.

The spelling of 406426820 in words is "four hundred six million, four hundred twenty-six thousand, eight hundred twenty".