217421270 has 24 divisors (see below), whose sum is σ = 430173072. Its totient is φ = 79061840.

The previous prime is 217421261. The next prime is 217421273. The reversal of 217421270 is 72124712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217421273) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 88634 + ... + 91053.

It is an arithmetic number, because the mean of its divisors is an integer number (17923878).

Almost surely, 2^217421270 is an apocalyptic number.

217421270 is a deficient number, since it is larger than the sum of its proper divisors (212751802).

217421270 is a wasteful number, since it uses less digits than its factorization.

217421270 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179716 (or 179705 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 26.

The square root of 217421270 is about 14745.2117651799. The cubic root of 217421270 is about 601.3131148599.

Adding to 217421270 its reverse (72124712), we get a palindrome (289545982).

The spelling of 217421270 in words is "two hundred seventeen million, four hundred twenty-one thousand, two hundred seventy".