28263431 has 8 divisors (see below), whose sum is σ = 34001280. Its totient is φ = 22950648.

The previous prime is 28263421. The next prime is 28263457. The reversal of 28263431 is 13436282.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-28263431 is a prime.

It is a super-2 number, since 2×28263431² = 1597643063783522, 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 = 28263394 and 28263403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28263421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 106121 + ... + 106386.

It is an arithmetic number, because the mean of its divisors is an integer number (4250160).

Almost surely, 2^28263431 is an apocalyptic number.

28263431 is a deficient number, since it is larger than the sum of its proper divisors (5737849).

28263431 is a wasteful number, since it uses less digits than its factorization.

28263431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212533.

The product of its digits is 6912, while the sum is 29.

The square root of 28263431 is about 5316.3362384259. The cubic root of 28263431 is about 304.6082258157.

The spelling of 28263431 in words is "twenty-eight million, two hundred sixty-three thousand, four hundred thirty-one".