421723566 has 96 divisors (see below), whose sum is σ = 1038974976. Its totient is φ = 122472000.

The previous prime is 421723553. The next prime is 421723579. The reversal of 421723566 is 665327124.

421723566 is a `hidden beast` number, since 4 + 21 + 72 + 3 + 566 = 666.

It is an interprime number because it is at equal distance from previous prime (421723553) and next prime (421723579).

It is a super-2 number, since 2×421723566² = 355701532239512712, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 421723566.

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 779256 + ... + 779796.

It is an arithmetic number, because the mean of its divisors is an integer number (10822656).

Almost surely, 2^421723566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 421723566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (519487488).

421723566 is an abundant number, since it is smaller than the sum of its proper divisors (617251410).

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

421723566 is a wasteful number, since it uses less digits than its factorization.

421723566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 718 (or 715 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 421723566 is about 20535.9091836714. The cubic root of 421723566 is about 749.9102505938.

The spelling of 421723566 in words is "four hundred twenty-one million, seven hundred twenty-three thousand, five hundred sixty-six".