28178684431 has 2 divisors, whose sum is σ = 28178684432. Its totient is φ = 28178684430.

The previous prime is 28178684411. The next prime is 28178684459. The reversal of 28178684431 is 13448687182.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28178684431 - 2⁵ = 28178684399 is a prime.

It is a super-2 number, since 2×28178684431² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28178684411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14089342215 + 14089342216.

It is an arithmetic number, because the mean of its divisors is an integer number (14089342216).

Almost surely, 2^28178684431 is an apocalyptic number.

28178684431 is a deficient number, since it is larger than the sum of its proper divisors (1).

28178684431 is an equidigital number, since it uses as much as digits as its factorization.

28178684431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2064384, while the sum is 52.

The spelling of 28178684431 in words is "twenty-eight billion, one hundred seventy-eight million, six hundred eighty-four thousand, four hundred thirty-one".