218650661712 has 640 divisors, whose sum is σ = 761094144000. Its totient is φ = 58794024960.

The previous prime is 218650661689. The next prime is 218650661767. The reversal of 218650661712 is 217166056812.

218650661712 is a `hidden beast` number, since 2 + 1 + 86 + 506 + 61 + 7 + 1 + 2 = 666.

It is a super-2 number, since 2×218650661712² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 609054589 + ... + 609054947.

It is an arithmetic number, because the mean of its divisors is an integer number (1189209600).

Almost surely, 2^218650661712 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218650661712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (380547072000).

218650661712 is an abundant number, since it is smaller than the sum of its proper divisors (542443482288).

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

218650661712 is a wasteful number, since it uses less digits than its factorization.

218650661712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576 (or 564 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 218650661712 in words is "two hundred eighteen billion, six hundred fifty million, six hundred sixty-one thousand, seven hundred twelve".