406321780 has 12 divisors (see below), whose sum is σ = 853275780. Its totient is φ = 162528704.

The previous prime is 406321771. The next prime is 406321787. The reversal of 406321780 is 87123604.

It can be written as a sum of positive squares in 2 ways, for example, as 253255396 + 153066384 = 15914^2 + 12372^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (406321787) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 10158025 + ... + 10158064.

It is an arithmetic number, because the mean of its divisors is an integer number (71106315).

Almost surely, 2^406321780 is an apocalyptic number.

It is an amenable number.

406321780 is an abundant number, since it is smaller than the sum of its proper divisors (446954000).

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

406321780 is a wasteful number, since it uses less digits than its factorization.

406321780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20316098 (or 20316096 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 406321780 is about 20157.4249347480. The cubic root of 406321780 is about 740.6676346290.

The spelling of 406321780 in words is "four hundred six million, three hundred twenty-one thousand, seven hundred eighty".