28131544608397 has 2 divisors, whose sum is σ = 28131544608398. Its totient is φ = 28131544608396.

The previous prime is 28131544608371. The next prime is 28131544608521. The reversal of 28131544608397 is 79380644513182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17137107810601 + 10994436797796 = 4139699^2 + 3315786^2 .

It is a cyclic number.

It is not a de Polignac number, because 28131544608397 - 2¹⁹ = 28131544084109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28131544608367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14065772304198 + 14065772304199.

It is an arithmetic number, because the mean of its divisors is an integer number (14065772304199).

It is a 2-persistent number, because it is pandigital, and so is 2⋅28131544608397 = 56263089216794, but 3⋅28131544608397 = 84394633825191 is not.

Almost surely, 2^{28131544608397} is an apocalyptic number.

It is an amenable number.

28131544608397 is a deficient number, since it is larger than the sum of its proper divisors (1).

28131544608397 is an equidigital number, since it uses as much as digits as its factorization.

28131544608397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34836480, while the sum is 61.

The spelling of 28131544608397 in words is "twenty-eight trillion, one hundred thirty-one billion, five hundred forty-four million, six hundred eight thousand, three hundred ninety-seven".