867493912871561 has 2 divisors, whose sum is σ = 867493912871562. Its totient is φ = 867493912871560.

The previous prime is 867493912871507. The next prime is 867493912871603. The reversal of 867493912871561 is 165178219394768.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 824560700977225 + 42933211894336 = 28715165^2 + 6552344^2 .

It is a cyclic number.

It is not a de Polignac number, because 867493912871561 - 2²² = 867493908677257 is a prime.

It is a super-2 number, since 2×867493912871561² (a number of 31 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (867493912877561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433746956435780 + 433746956435781.

It is an arithmetic number, because the mean of its divisors is an integer number (433746956435781).

Almost surely, 2^{867493912871561} is an apocalyptic number.

It is an amenable number.

867493912871561 is a deficient number, since it is larger than the sum of its proper divisors (1).

867493912871561 is an equidigital number, since it uses as much as digits as its factorization.

867493912871561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1097349120, while the sum is 77.

The spelling of 867493912871561 in words is "eight hundred sixty-seven trillion, four hundred ninety-three billion, nine hundred twelve million, eight hundred seventy-one thousand, five hundred sixty-one".