13856120217 has 24 divisors (see below), whose sum is σ = 20313681024. Its totient is φ = 9100214784.

The previous prime is 13856120167. The next prime is 13856120219. The reversal of 13856120217 is 71202165831.

13856120217 is a `hidden beast` number, since 1 + 38 + 5 + 612 + 0 + 2 + 1 + 7 = 666.

It is not a de Polignac number, because 13856120217 - 2¹⁵ = 13856087449 is a prime.

It is a super-2 number, since 2×13856120217² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13856120219) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 140188 + ... + 217634.

It is an arithmetic number, because the mean of its divisors is an integer number (846403376).

Almost surely, 2^13856120217 is an apocalyptic number.

It is an amenable number.

13856120217 is a deficient number, since it is larger than the sum of its proper divisors (6457560807).

13856120217 is a wasteful number, since it uses less digits than its factorization.

13856120217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77749 (or 77746 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The spelling of 13856120217 in words is "thirteen billion, eight hundred fifty-six million, one hundred twenty thousand, two hundred seventeen".