400646506 has 16 divisors (see below), whose sum is σ = 662985288. Its totient is φ = 180403200.

The previous prime is 400646503. The next prime is 400646537. The reversal of 400646506 is 605646004.

It can be written as a sum of positive squares in 4 ways, for example, as 254115481 + 146531025 = 15941^2 + 12105^2 .

It is not an unprimeable number, because it can be changed into a prime (400646503) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 186855 + ... + 188986.

Almost surely, 2^400646506 is an apocalyptic number.

400646506 is a deficient number, since it is larger than the sum of its proper divisors (262338782).

400646506 is a wasteful number, since it uses less digits than its factorization.

400646506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375897.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 400646506 is about 20016.1561244910. The cubic root of 400646506 is about 737.2030441348.

The spelling of 400646506 in words is "four hundred million, six hundred forty-six thousand, five hundred six".