217420144 has 10 divisors (see below), whose sum is σ = 421251560. Its totient is φ = 108710064.

The previous prime is 217420117. The next prime is 217420153. The reversal of 217420144 is 441024712.

217420144 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×217420144³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6794364 + ... + 6794395.

It is an arithmetic number, because the mean of its divisors is an integer number (42125156).

Almost surely, 2^217420144 is an apocalyptic number.

It is an amenable number.

217420144 is a deficient number, since it is larger than the sum of its proper divisors (203831416).

217420144 is a wasteful number, since it uses less digits than its factorization.

217420144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13588767 (or 13588761 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 217420144 is about 14745.1735832441. The cubic root of 217420144 is about 601.3120768141.

Adding to 217420144 its reverse (441024712), we get a palindrome (658444856).

The spelling of 217420144 in words is "two hundred seventeen million, four hundred twenty thousand, one hundred forty-four".