400016556 has 60 divisors (see below), whose sum is σ = 1060511760. Its totient is φ = 131453280.

The previous prime is 400016527. The next prime is 400016581. The reversal of 400016556 is 655610004.

It is a happy number.

400016556 is a `hidden beast` number, since 4 + 0 + 0 + 0 + 1 + 655 + 6 = 666.

It is a super-2 number, since 2×400016556² = 320026490148202272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 19 ways as a sum of consecutive naturals, for example, 14310 + ... + 31698.

It is an arithmetic number, because the mean of its divisors is an integer number (17675196).

Almost surely, 2^400016556 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 400016556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (530255880).

400016556 is an abundant number, since it is smaller than the sum of its proper divisors (660495204).

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

400016556 is a wasteful number, since it uses less digits than its factorization.

400016556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17476 (or 17465 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 400016556 is about 20000.4138957173. The cubic root of 400016556 is about 736.8164650587.

The spelling of 400016556 in words is "four hundred million, sixteen thousand, five hundred fifty-six".