216631800 has 384 divisors, whose sum is σ = 932083200. Its totient is φ = 44928000.

The previous prime is 216631783. The next prime is 216631843. The reversal of 216631800 is 8136612.

216631800 is a `hidden beast` number, since 21 + 6 + 631 + 8 + 0 + 0 = 666.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 415540 + ... + 416060.

It is an arithmetic number, because the mean of its divisors is an integer number (2427300).

Almost surely, 2^216631800 is an apocalyptic number.

216631800 is a gapful number since it is divisible by the number (20) 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 216631800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (466041600).

216631800 is an abundant number, since it is smaller than the sum of its proper divisors (715451400).

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

216631800 is a wasteful number, since it uses less digits than its factorization.

216631800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 564 (or 549 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 216631800 is about 14718.4170344504. The cubic root of 216631800 is about 600.5844305501.

The spelling of 216631800 in words is "two hundred sixteen million, six hundred thirty-one thousand, eight hundred".