28121260531 has 64 divisors (see below), whose sum is σ = 36905137920. Its totient is φ = 20832215040.

The previous prime is 28121260511. The next prime is 28121260567. The reversal of 28121260531 is 13506212182.

It is not a de Polignac number, because 28121260531 - 2¹⁹ = 28120736243 is a prime.

It is a super-2 number, since 2×28121260531² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28121260493 and 28121260502.

It is not an unprimeable number, because it can be changed into a prime (28121260511) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11750271 + ... + 11752663.

It is an arithmetic number, because the mean of its divisors is an integer number (576642780).

Almost surely, 2^28121260531 is an apocalyptic number.

28121260531 is a deficient number, since it is larger than the sum of its proper divisors (8783877389).

28121260531 is a wasteful number, since it uses less digits than its factorization.

28121260531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2576.

The product of its (nonzero) digits is 5760, while the sum is 31.

The spelling of 28121260531 in words is "twenty-eight billion, one hundred twenty-one million, two hundred sixty thousand, five hundred thirty-one".