68613518661381 has 20 divisors (see below), whose sum is σ = 102501729614592. Its totient is φ = 45740118001608.

The previous prime is 68613518661361. The next prime is 68613518661409. The reversal of 68613518661381 is 18316681531686.

It is a happy number.

68613518661381 is a `hidden beast` number, since 6 + 8 + 6 + 1 + 3 + 5 + 1 + 8 + 6 + 613 + 8 + 1 = 666.

It is not a de Polignac number, because 68613518661381 - 2¹¹ = 68613518659333 is a prime.

It is a super-2 number, since 2×68613518661381² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68613518661341) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 18953271 + ... + 22281236.

Almost surely, 2^{68613518661381} is an apocalyptic number.

It is an amenable number.

68613518661381 is a deficient number, since it is larger than the sum of its proper divisors (33888210953211).

68613518661381 is a wasteful number, since it uses less digits than its factorization.

68613518661381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41255062 (or 41255053 counting only the distinct ones).

The product of its digits is 29859840, while the sum is 63.

The spelling of 68613518661381 in words is "sixty-eight trillion, six hundred thirteen billion, five hundred eighteen million, six hundred sixty-one thousand, three hundred eighty-one".