28781320123 has 8 divisors (see below), whose sum is σ = 29138606000. Its totient is φ = 28426180608.

The previous prime is 28781320081. The next prime is 28781320133. The reversal of 28781320123 is 32102318782.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28781320123 - 2²⁵ = 28747765691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28781320133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 509598 + ... + 563251.

It is an arithmetic number, because the mean of its divisors is an integer number (3642325750).

Almost surely, 2^28781320123 is an apocalyptic number.

28781320123 is a deficient number, since it is larger than the sum of its proper divisors (357285877).

28781320123 is a wasteful number, since it uses less digits than its factorization.

28781320123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1073181.

The product of its (nonzero) digits is 32256, while the sum is 37.

The spelling of 28781320123 in words is "twenty-eight billion, seven hundred eighty-one million, three hundred twenty thousand, one hundred twenty-three".