217812672 has 224 divisors, whose sum is σ = 798819840. Its totient is φ = 56540160.

The previous prime is 217812671. The next prime is 217812677. The reversal of 217812672 is 276218712.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (217812671) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 132238 + ... + 133874.

It is an arithmetic number, because the mean of its divisors is an integer number (3566160).

Almost surely, 2^217812672 is an apocalyptic number.

217812672 is a gapful number since it is divisible by the number (22) 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 217812672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (399409920).

217812672 is an abundant number, since it is smaller than the sum of its proper divisors (581007168).

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

217812672 is a wasteful number, since it uses less digits than its factorization.

217812672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1676 (or 1660 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 217812672 is about 14758.4779703057. The cubic root of 217812672 is about 601.6737267234.

The spelling of 217812672 in words is "two hundred seventeen million, eight hundred twelve thousand, six hundred seventy-two".