68138173861 has 2 divisors, whose sum is σ = 68138173862. Its totient is φ = 68138173860.

The previous prime is 68138173837. The next prime is 68138173889. The reversal of 68138173861 is 16837183186.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 56837420836 + 11300753025 = 238406^2 + 106305^2 .

It is a cyclic number.

It is not a de Polignac number, because 68138173861 - 2¹⁷ = 68138042789 is a prime.

It is a super-2 number, since 2×68138173861² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 68138173799 and 68138173808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68138173801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34069086930 + 34069086931.

It is an arithmetic number, because the mean of its divisors is an integer number (34069086931).

Almost surely, 2^68138173861 is an apocalyptic number.

It is an amenable number.

68138173861 is a deficient number, since it is larger than the sum of its proper divisors (1).

68138173861 is an equidigital number, since it uses as much as digits as its factorization.

68138173861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1161216, while the sum is 52.

The spelling of 68138173861 in words is "sixty-eight billion, one hundred thirty-eight million, one hundred seventy-three thousand, eight hundred sixty-one".