28251431 has 8 divisors (see below), whose sum is σ = 30473184. Its totient is φ = 26036640.

The previous prime is 28251413. The next prime is 28251493. The reversal of 28251431 is 13415282.

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

It is a cyclic number.

It is not a de Polignac number, because 28251431 - 2¹⁸ = 27989287 is a prime.

It is a super-2 number, since 2×28251431² = 1596286707095522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28251431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28251401) 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, 9350 + ... + 11996.

It is an arithmetic number, because the mean of its divisors is an integer number (3809148).

Almost surely, 2^28251431 is an apocalyptic number.

28251431 is a deficient number, since it is larger than the sum of its proper divisors (2221753).

28251431 is a wasteful number, since it uses less digits than its factorization.

28251431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3481.

The product of its digits is 1920, while the sum is 26.

The square root of 28251431 is about 5315.2075218189. The cubic root of 28251431 is about 304.5651098407.

It can be divided in two parts, 28251 and 431, that added together give a palindrome (28682).

The spelling of 28251431 in words is "twenty-eight million, two hundred fifty-one thousand, four hundred thirty-one".