28737648778 has 4 divisors (see below), whose sum is σ = 43106473170. Its totient is φ = 14368824388.

The previous prime is 28737648767. The next prime is 28737648781. The reversal of 28737648778 is 87784673782.

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

It can be written as a sum of positive squares in only one way, i.e., 22050171049 + 6687477729 = 148493^2 + 81777^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7184412193 + ... + 7184412196.

Almost surely, 2^28737648778 is an apocalyptic number.

28737648778 is a deficient number, since it is larger than the sum of its proper divisors (14368824392).

28737648778 is a wasteful number, since it uses less digits than its factorization.

28737648778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14368824391.

The product of its digits is 177020928, while the sum is 67.

The spelling of 28737648778 in words is "twenty-eight billion, seven hundred thirty-seven million, six hundred forty-eight thousand, seven hundred seventy-eight".