218738414477 has 4 divisors (see below), whose sum is σ = 238623724896. Its totient is φ = 198853104060.

The previous prime is 218738414471. The next prime is 218738414509. The reversal of 218738414477 is 774414837812.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-218738414477 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 (218738414471) 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, 9942655193 + ... + 9942655214.

It is an arithmetic number, because the mean of its divisors is an integer number (59655931224).

Almost surely, 2^218738414477 is an apocalyptic number.

It is an amenable number.

218738414477 is a deficient number, since it is larger than the sum of its proper divisors (19885310419).

218738414477 is a wasteful number, since it uses less digits than its factorization.

218738414477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19885310418.

The product of its digits is 8429568, while the sum is 56.

The spelling of 218738414477 in words is "two hundred eighteen billion, seven hundred thirty-eight million, four hundred fourteen thousand, four hundred seventy-seven".