217215050520 has 128 divisors (see below), whose sum is σ = 738707155200. Its totient is φ = 50654191104.

The previous prime is 217215050497. The next prime is 217215050551. The reversal of 217215050520 is 25050512712.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3634582 + ... + 3693861.

It is an arithmetic number, because the mean of its divisors is an integer number (5771149650).

Almost surely, 2^217215050520 is an apocalyptic number.

217215050520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217215050520 is an abundant number, since it is smaller than the sum of its proper divisors (521492104680).

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

217215050520 is a wasteful number, since it uses less digits than its factorization.

217215050520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7328489 (or 7328485 counting only the distinct ones).

The product of its (nonzero) digits is 7000, while the sum is 30.

The spelling of 217215050520 in words is "two hundred seventeen billion, two hundred fifteen million, fifty thousand, five hundred twenty".