28911420431 has 4 divisors (see below), whose sum is σ = 28918036152. Its totient is φ = 28904804712.

The previous prime is 28911420407. The next prime is 28911420449. The reversal of 28911420431 is 13402411982.

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 28911420431 - 2⁶ = 28911420367 is a prime.

It is a super-2 number, since 2×28911420431² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28911420391 and 28911420400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28911420451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3301301 + ... + 3310046.

It is an arithmetic number, because the mean of its divisors is an integer number (7229509038).

Almost surely, 2^28911420431 is an apocalyptic number.

28911420431 is a deficient number, since it is larger than the sum of its proper divisors (6615721).

28911420431 is an equidigital number, since it uses as much as digits as its factorization.

28911420431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6615720.

The product of its (nonzero) digits is 13824, while the sum is 35.

The spelling of 28911420431 in words is "twenty-eight billion, nine hundred eleven million, four hundred twenty thousand, four hundred thirty-one".