217747292820 has 48 divisors (see below), whose sum is σ = 629359922688. Its totient is φ = 56192849280.

The previous prime is 217747292813. The next prime is 217747292849. The reversal of 217747292820 is 28292747712.

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58532359 + ... + 58536078.

It is an arithmetic number, because the mean of its divisors is an integer number (13111665056).

Almost surely, 2^217747292820 is an apocalyptic number.

217747292820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217747292820 is an abundant number, since it is smaller than the sum of its proper divisors (411612629868).

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

217747292820 is a wasteful number, since it uses less digits than its factorization.

217747292820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117068480 (or 117068478 counting only the distinct ones).

The product of its (nonzero) digits is 1580544, while the sum is 51.

The spelling of 217747292820 in words is "two hundred seventeen billion, seven hundred forty-seven million, two hundred ninety-two thousand, eight hundred twenty".