55218538667 has 4 divisors (see below), whose sum is σ = 57619344720. Its totient is φ = 52817732616.

The previous prime is 55218538657. The next prime is 55218538679. The reversal of 55218538667 is 76683581255.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76683581255 = 5 ⋅15336716251.

It is a cyclic number.

It is not a de Polignac number, because 55218538667 - 2⁶ = 55218538603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55218538637) 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, 1200402992 + ... + 1200403037.

It is an arithmetic number, because the mean of its divisors is an integer number (14404836180).

Almost surely, 2^55218538667 is an apocalyptic number.

55218538667 is a deficient number, since it is larger than the sum of its proper divisors (2400806053).

55218538667 is a wasteful number, since it uses less digits than its factorization.

55218538667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2400806052.

The product of its digits is 12096000, while the sum is 56.

The spelling of 55218538667 in words is "fifty-five billion, two hundred eighteen million, five hundred thirty-eight thousand, six hundred sixty-seven".