28400055779 has 2 divisors, whose sum is σ = 28400055780. Its totient is φ = 28400055778.

The previous prime is 28400055679. The next prime is 28400055797. The reversal of 28400055779 is 97755000482.

It is a happy number.

Together with next prime (28400055797) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28400055779 - 2²⁸ = 28131620323 is a prime.

It is a super-2 number, since 2×28400055779² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (28400055179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14200027889 + 14200027890.

It is an arithmetic number, because the mean of its divisors is an integer number (14200027890).

Almost surely, 2^28400055779 is an apocalyptic number.

28400055779 is a deficient number, since it is larger than the sum of its proper divisors (1).

28400055779 is an equidigital number, since it uses as much as digits as its factorization.

28400055779 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 705600, while the sum is 47.

The spelling of 28400055779 in words is "twenty-eight billion, four hundred million, fifty-five thousand, seven hundred seventy-nine".