217072944 has 120 divisors (see below), whose sum is σ = 678355392. Its totient is φ = 64229760.

The previous prime is 217072939. The next prime is 217072991. The reversal of 217072944 is 449270712.

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

It is a junction number, because it is equal to n+sod(n) for n = 217072899 and 217072908.

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 23 ways as a sum of consecutive naturals, for example, 66519 + ... + 69705.

Almost surely, 2^217072944 is an apocalyptic number.

217072944 is a gapful number since it is divisible by the number (24) 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 217072944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (339177696).

217072944 is an abundant number, since it is smaller than the sum of its proper divisors (461282448).

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

217072944 is a wasteful number, since it uses less digits than its factorization.

217072944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3255 (or 3246 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 217072944 is about 14733.3955353136. The cubic root of 217072944 is about 600.9918262311.

The spelling of 217072944 in words is "two hundred seventeen million, seventy-two thousand, nine hundred forty-four".