217612065550 has 48 divisors (see below), whose sum is σ = 455798398464. Its totient is φ = 76579020000.

The previous prime is 217612065547. The next prime is 217612065551. The reversal of 217612065550 is 55560216712.

It is a super-2 number, since 2×217612065550² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217612065551) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6364536 + ... + 6398635.

It is an arithmetic number, because the mean of its divisors is an integer number (9495799968).

Almost surely, 2^217612065550 is an apocalyptic number.

217612065550 is an abundant number, since it is smaller than the sum of its proper divisors (238186332914).

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

217612065550 is a wasteful number, since it uses less digits than its factorization.

217612065550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12763225 (or 12763220 counting only the distinct ones).

The product of its (nonzero) digits is 126000, while the sum is 40.

The spelling of 217612065550 in words is "two hundred seventeen billion, six hundred twelve million, sixty-five thousand, five hundred fifty".