217429870 has 48 divisors (see below), whose sum is σ = 453214944. Its totient is φ = 73569600.

The previous prime is 217429867. The next prime is 217429897. The reversal of 217429870 is 78924712.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1201180 + ... + 1201360.

It is an arithmetic number, because the mean of its divisors is an integer number (9441978).

Almost surely, 2^217429870 is an apocalyptic number.

217429870 is an abundant number, since it is smaller than the sum of its proper divisors (235785074).

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

217429870 is a wasteful number, since it uses less digits than its factorization.

217429870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457 (or 326 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 217429870 is about 14745.5033823875. The cubic root of 217429870 is about 601.3210429781.

The spelling of 217429870 in words is "two hundred seventeen million, four hundred twenty-nine thousand, eight hundred seventy".