218135566890 has 192 divisors, whose sum is σ = 639089418240. Its totient is φ = 53329907520.

The previous prime is 218135566879. The next prime is 218135566919. The reversal of 218135566890 is 98665531812.

218135566890 is a `hidden beast` number, since 2 + 1 + 8 + 1 + 3 + 556 + 6 + 89 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1355067 + ... + 1507473.

It is an arithmetic number, because the mean of its divisors is an integer number (3328590720).

Almost surely, 2^218135566890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218135566890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319544709120).

218135566890 is an abundant number, since it is smaller than the sum of its proper divisors (420953851350).

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

218135566890 is a wasteful number, since it uses less digits than its factorization.

218135566890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152479 (or 152467 counting only the distinct ones).

The product of its (nonzero) digits is 3110400, while the sum is 54.

The spelling of 218135566890 in words is "two hundred eighteen billion, one hundred thirty-five million, five hundred sixty-six thousand, eight hundred ninety".