28720612811 has 16 divisors (see below), whose sum is σ = 33457536000. Its totient is φ = 24396103200.

The previous prime is 28720612801. The next prime is 28720612867. The reversal of 28720612811 is 11821602782.

It is a cyclic number.

It is not a de Polignac number, because 28720612811 - 2¹⁴ = 28720596427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28720612801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1442261 + ... + 1462038.

It is an arithmetic number, because the mean of its divisors is an integer number (2091096000).

Almost surely, 2^28720612811 is an apocalyptic number.

28720612811 is a deficient number, since it is larger than the sum of its proper divisors (4736923189).

28720612811 is a wasteful number, since it uses less digits than its factorization.

28720612811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2904370.

The product of its (nonzero) digits is 21504, while the sum is 38.

The spelling of 28720612811 in words is "twenty-eight billion, seven hundred twenty million, six hundred twelve thousand, eight hundred eleven".