6861621164077 has 2 divisors, whose sum is σ = 6861621164078. Its totient is φ = 6861621164076.

The previous prime is 6861621164059. The next prime is 6861621164117. The reversal of 6861621164077 is 7704611261686.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5125179820996 + 1736441343081 = 2263886^2 + 1317741^2 .

It is a cyclic number.

It is not a de Polignac number, because 6861621164077 - 2⁷ = 6861621163949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6861621164777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3430810582038 + 3430810582039.

It is an arithmetic number, because the mean of its divisors is an integer number (3430810582039).

Almost surely, 2^{6861621164077} is an apocalyptic number.

It is an amenable number.

6861621164077 is a deficient number, since it is larger than the sum of its proper divisors (1).

6861621164077 is an equidigital number, since it uses as much as digits as its factorization.

6861621164077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4064256, while the sum is 55.

The spelling of 6861621164077 in words is "six trillion, eight hundred sixty-one billion, six hundred twenty-one million, one hundred sixty-four thousand, seventy-seven".