28821178747481 has 2 divisors, whose sum is σ = 28821178747482. Its totient is φ = 28821178747480.

The previous prime is 28821178747447. The next prime is 28821178747507. The reversal of 28821178747481 is 18474787112882.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25232488008025 + 3588690739456 = 5023195^2 + 1894384^2 .

It is a cyclic number.

It is not a de Polignac number, because 28821178747481 - 2¹⁰ = 28821178746457 is a prime.

It is a super-2 number, since 2×28821178747481² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28821178744481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14410589373740 + 14410589373741.

It is an arithmetic number, because the mean of its divisors is an integer number (14410589373741).

Almost surely, 2^{28821178747481} is an apocalyptic number.

It is an amenable number.

28821178747481 is a deficient number, since it is larger than the sum of its proper divisors (1).

28821178747481 is an equidigital number, since it uses as much as digits as its factorization.

28821178747481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 89915392, while the sum is 68.

The spelling of 28821178747481 in words is "twenty-eight trillion, eight hundred twenty-one billion, one hundred seventy-eight million, seven hundred forty-seven thousand, four hundred eighty-one".