28431432231 has 4 divisors (see below), whose sum is σ = 37908576312. Its totient is φ = 18954288152.

The previous prime is 28431432223. The next prime is 28431432251. The reversal of 28431432231 is 13223413482.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28431432231 - 2³ = 28431432223 is a prime.

It is a super-2 number, since 2×28431432231² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28431432192 and 28431432201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28431432251) 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 3 ways as a sum of consecutive naturals, for example, 4738572036 + ... + 4738572041.

It is an arithmetic number, because the mean of its divisors is an integer number (9477144078).

Almost surely, 2^28431432231 is an apocalyptic number.

28431432231 is a deficient number, since it is larger than the sum of its proper divisors (9477144081).

28431432231 is an equidigital number, since it uses as much as digits as its factorization.

28431432231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9477144080.

The product of its digits is 27648, while the sum is 33.

The spelling of 28431432231 in words is "twenty-eight billion, four hundred thirty-one million, four hundred thirty-two thousand, two hundred thirty-one".