218542020777 has 12 divisors (see below), whose sum is σ = 316566066804. Its totient is φ = 145281945600.

The previous prime is 218542020769. The next prime is 218542020797. The reversal of 218542020777 is 777020245812.

218542020777 is a `hidden beast` number, since 2 + 18 + 5 + 420 + 207 + 7 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 45969075216 + 172572945561 = 214404^2 + 415419^2 .

It is not a de Polignac number, because 218542020777 - 2³ = 218542020769 is a prime.

It is a super-2 number, since 2×218542020777² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (218542020707) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34391224 + ... + 34397577.

It is an arithmetic number, because the mean of its divisors is an integer number (26380505567).

Almost surely, 2^218542020777 is an apocalyptic number.

It is an amenable number.

218542020777 is a deficient number, since it is larger than the sum of its proper divisors (98024046027).

218542020777 is a wasteful number, since it uses less digits than its factorization.

218542020777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68789160 (or 68789157 counting only the distinct ones).

The product of its (nonzero) digits is 439040, while the sum is 45.

The spelling of 218542020777 in words is "two hundred eighteen billion, five hundred forty-two million, twenty thousand, seven hundred seventy-seven".