28778072664 has 64 divisors (see below), whose sum is σ = 79084874880. Its totient is φ = 8654048000.

The previous prime is 28778072641. The next prime is 28778072671. The reversal of 28778072664 is 46627087782.

It is a congruent number.

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 in 15 ways as a sum of consecutive naturals, for example, 381477 + ... + 450644.

It is an arithmetic number, because the mean of its divisors is an integer number (1235701170).

Almost surely, 2^28778072664 is an apocalyptic number.

28778072664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28778072664 is an abundant number, since it is smaller than the sum of its proper divisors (50306802216).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28778072664 is a wasteful number, since it uses less digits than its factorization.

28778072664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 832272 (or 832268 counting only the distinct ones).

The product of its (nonzero) digits is 12644352, while the sum is 57.

The spelling of 28778072664 in words is "twenty-eight billion, seven hundred seventy-eight million, seventy-two thousand, six hundred sixty-four".