10891749895561 has 2 divisors, whose sum is σ = 10891749895562. Its totient is φ = 10891749895560.

The previous prime is 10891749895517. The next prime is 10891749895567. The reversal of 10891749895561 is 16559894719801.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10177733345536 + 714016550025 = 3190256^2 + 844995^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10891749895561 is a prime.

It is a super-3 number, since 3×10891749895561³ (a number of 40 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (10891749895567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5445874947780 + 5445874947781.

It is an arithmetic number, because the mean of its divisors is an integer number (5445874947781).

Almost surely, 2^{10891749895561} is an apocalyptic number.

It is an amenable number.

10891749895561 is a deficient number, since it is larger than the sum of its proper divisors (1).

10891749895561 is an equidigital number, since it uses as much as digits as its factorization.

10891749895561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 195955200, while the sum is 73.

The spelling of 10891749895561 in words is "ten trillion, eight hundred ninety-one billion, seven hundred forty-nine million, eight hundred ninety-five thousand, five hundred sixty-one".