406434640 has 160 divisors (see below), whose sum is σ = 1057994784. Its totient is φ = 144506880.

The previous prime is 406434629. The next prime is 406434683. The reversal of 406434640 is 46434604.

It can be written as a sum of positive squares in 16 ways, for example, as 976144 + 405458496 = 988^2 + 20136^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2063022 + ... + 2063218.

Almost surely, 2^406434640 is an apocalyptic number.

406434640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 406434640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (528997392).

406434640 is an abundant number, since it is smaller than the sum of its proper divisors (651560144).

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

406434640 is a wasteful number, since it uses less digits than its factorization.

406434640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305 (or 299 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 31.

The square root of 406434640 is about 20160.2242051025. The cubic root of 406434640 is about 740.7362042660.

The spelling of 406434640 in words is "four hundred six million, four hundred thirty-four thousand, six hundred forty".