218861055 has 32 divisors (see below), whose sum is σ = 444672000. Its totient is φ = 100050336.

The previous prime is 218861051. The next prime is 218861087. The reversal of 218861055 is 550168812.

It is not a de Polignac number, because 218861055 - 2² = 218861051 is a prime.

It is a super-2 number, since 2×218861055² = 95800322791426050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218861051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 114855 + ... + 116744.

It is an arithmetic number, because the mean of its divisors is an integer number (13896000).

Almost surely, 2^218861055 is an apocalyptic number.

218861055 is an abundant number, since it is smaller than the sum of its proper divisors (225810945).

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

218861055 is a wasteful number, since it uses less digits than its factorization.

218861055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231620 (or 231614 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 36.

The square root of 218861055 is about 14793.9533255989. The cubic root of 218861055 is about 602.6375138789.

The spelling of 218861055 in words is "two hundred eighteen million, eight hundred sixty-one thousand, fifty-five".