217390000 has 50 divisors (see below), whose sum is σ = 526347140. Its totient is φ = 86952000.

The previous prime is 217389979. The next prime is 217390007. The reversal of 217390000 is 93712.

It is a tau number, because it is divible by the number of its divisors (50).

It is not an unprimeable number, because it can be changed into a prime (217390007) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 870 + ... + 20869.

Almost surely, 2^217390000 is an apocalyptic number.

217390000 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 217390000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263173570).

217390000 is an abundant number, since it is smaller than the sum of its proper divisors (308957140).

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

217390000 is an equidigital number, since it uses as much as digits as its factorization.

217390000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21767 (or 21746 counting only the distinct ones).

The product of its (nonzero) digits is 378, while the sum is 22.

The square root of 217390000 is about 14744.1513828365. The cubic root of 217390000 is about 601.2842860911.

The spelling of 217390000 in words is "two hundred seventeen million, three hundred ninety thousand".