28315749557 has 2 divisors, whose sum is σ = 28315749558. Its totient is φ = 28315749556.

The previous prime is 28315749523. The next prime is 28315749589. The reversal of 28315749557 is 75594751382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27888666001 + 427083556 = 166999^2 + 20666^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28315749557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28315749157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14157874778 + 14157874779.

It is an arithmetic number, because the mean of its divisors is an integer number (14157874779).

Almost surely, 2^28315749557 is an apocalyptic number.

It is an amenable number.

28315749557 is a deficient number, since it is larger than the sum of its proper divisors (1).

28315749557 is an equidigital number, since it uses as much as digits as its factorization.

28315749557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584000, while the sum is 56.

The spelling of 28315749557 in words is "twenty-eight billion, three hundred fifteen million, seven hundred forty-nine thousand, five hundred fifty-seven".