402205640 has 64 divisors (see below), whose sum is σ = 945054000. Its totient is φ = 153861120.

The previous prime is 402205621. The next prime is 402205667. The reversal of 402205640 is 46502204.

It can be written as a sum of positive squares in 8 ways, for example, as 118417924 + 283787716 = 10882^2 + 16846^2 .

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 124850 + ... + 128030.

Almost surely, 2^402205640 is an apocalyptic number.

402205640 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 402205640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (472527000).

402205640 is an abundant number, since it is smaller than the sum of its proper divisors (542848360).

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

402205640 is a wasteful number, since it uses less digits than its factorization.

402205640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3330 (or 3326 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 402205640 is about 20055.0651956058. The cubic root of 402205640 is about 738.1580926629.

Adding to 402205640 its reverse (46502204), we get a palindrome (448707844).

The spelling of 402205640 in words is "four hundred two million, two hundred five thousand, six hundred forty".