28269431 has 6 divisors (see below), whose sum is σ = 28713096. Its totient is φ = 27827100.

The previous prime is 28269401. The next prime is 28269491. The reversal of 28269431 is 13496282.

It is a de Polignac number, because none of the positive numbers 2^k-28269431 is a prime.

It is a super-2 number, since 2×28269431² = 1598321458127522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28269391 and 28269400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28269401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 44486 + ... + 45116.

It is an arithmetic number, because the mean of its divisors is an integer number (4785516).

Almost surely, 2^28269431 is an apocalyptic number.

28269431 is a deficient number, since it is larger than the sum of its proper divisors (443665).

28269431 is an frugal number, since it uses more digits than its factorization.

28269431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1333 (or 702 counting only the distinct ones).

The product of its digits is 20736, while the sum is 35.

The square root of 28269431 is about 5316.9005068743. The cubic root of 28269431 is about 304.6297792268.

The spelling of 28269431 in words is "twenty-eight million, two hundred sixty-nine thousand, four hundred thirty-one".