218561101 has 4 divisors (see below), whose sum is σ = 238430304. Its totient is φ = 198691900.

The previous prime is 218561093. The next prime is 218561117. The reversal of 218561101 is 101165812.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 218561101 - 2³ = 218561093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218561171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9934585 + ... + 9934606.

It is an arithmetic number, because the mean of its divisors is an integer number (59607576).

Almost surely, 2^218561101 is an apocalyptic number.

It is an amenable number.

218561101 is a deficient number, since it is larger than the sum of its proper divisors (19869203).

218561101 is a wasteful number, since it uses less digits than its factorization.

218561101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19869202.

The product of its (nonzero) digits is 480, while the sum is 25.

The square root of 218561101 is about 14783.8121267825. The cubic root of 218561101 is about 602.3620785866.

The spelling of 218561101 in words is "two hundred eighteen million, five hundred sixty-one thousand, one hundred one".