420172866 has 64 divisors (see below), whose sum is σ = 971942400. Its totient is φ = 134437968.

The previous prime is 420172813. The next prime is 420172871. The reversal of 420172866 is 668271024.

420172866 is a `hidden beast` number, since 420 + 172 + 8 + 66 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 420172866.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 135465 + ... + 138531.

It is an arithmetic number, because the mean of its divisors is an integer number (15186600).

Almost surely, 2^420172866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 420172866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (485971200).

420172866 is an abundant number, since it is smaller than the sum of its proper divisors (551769534).

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

420172866 is a wasteful number, since it uses less digits than its factorization.

420172866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3180 (or 3174 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 420172866 is about 20498.1185965932. The cubic root of 420172866 is about 748.9899683921.

The spelling of 420172866 in words is "four hundred twenty million, one hundred seventy-two thousand, eight hundred sixty-six".