218265013638 has 160 divisors (see below), whose sum is σ = 573152025600. Its totient is φ = 60779237760.

The previous prime is 218265013579. The next prime is 218265013723. The reversal of 218265013638 is 836310562812.

218265013638 is a `hidden beast` number, since 2 + 1 + 8 + 2 + 6 + 5 + 0 + 1 + 3 + 638 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 218265013593 and 218265013602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 66159313 + ... + 66162611.

It is an arithmetic number, because the mean of its divisors is an integer number (3582200160).

Almost surely, 2^218265013638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218265013638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (286576012800).

218265013638 is an abundant number, since it is smaller than the sum of its proper divisors (354887011962).

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

218265013638 is a wasteful number, since it uses less digits than its factorization.

218265013638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4784 (or 4775 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The spelling of 218265013638 in words is "two hundred eighteen billion, two hundred sixty-five million, thirteen thousand, six hundred thirty-eight".