28272572781 has 16 divisors (see below), whose sum is σ = 38379446784. Its totient is φ = 18509760944.

The previous prime is 28272572777. The next prime is 28272572803. The reversal of 28272572781 is 18727527282.

It is not a de Polignac number, because 28272572781 - 2² = 28272572777 is a prime.

It is a super-2 number, since 2×28272572781² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28272572701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 298371 + ... + 381536.

It is an arithmetic number, because the mean of its divisors is an integer number (2398715424).

Almost surely, 2^28272572781 is an apocalyptic number.

It is an amenable number.

28272572781 is a deficient number, since it is larger than the sum of its proper divisors (10106874003).

28272572781 is a wasteful number, since it uses less digits than its factorization.

28272572781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680160.

The product of its digits is 1756160, while the sum is 51.

The spelling of 28272572781 in words is "twenty-eight billion, two hundred seventy-two million, five hundred seventy-two thousand, seven hundred eighty-one".