28891051108669 has 4 divisors (see below), whose sum is σ = 28995350932444. Its totient is φ = 28786751284896.

The previous prime is 28891051108663. The next prime is 28891051108741. The reversal of 28891051108669 is 96680115019882.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16428470772025 + 12462580336644 = 4053205^2 + 3530238^2 .

It is a cyclic number.

It is not a de Polignac number, because 28891051108669 - 2⁵ = 28891051108637 is a prime.

It is a super-2 number, since 2×28891051108669² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28891051108669.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28891051108663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52149911472 + ... + 52149912025.

It is an arithmetic number, because the mean of its divisors is an integer number (7248837733111).

Almost surely, 2^{28891051108669} is an apocalyptic number.

It is an amenable number.

28891051108669 is a deficient number, since it is larger than the sum of its proper divisors (104299823775).

28891051108669 is a wasteful number, since it uses less digits than its factorization.

28891051108669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104299823774.

The product of its (nonzero) digits is 14929920, while the sum is 64.

The spelling of 28891051108669 in words is "twenty-eight trillion, eight hundred ninety-one billion, fifty-one million, one hundred eight thousand, six hundred sixty-nine".