28045431 has 6 divisors (see below), whose sum is σ = 40510080. Its totient is φ = 18696948.

The previous prime is 28045403. The next prime is 28045447. The reversal of 28045431 is 13454082.

It is a de Polignac number, because none of the positive numbers 2^k-28045431 is a prime.

It is a super-2 number, since 2×28045431² = 1573092399951522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28045395 and 28045404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28045471) 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, 1558071 + ... + 1558088.

It is an arithmetic number, because the mean of its divisors is an integer number (6751680).

Almost surely, 2^28045431 is an apocalyptic number.

28045431 is a deficient number, since it is larger than the sum of its proper divisors (12464649).

28045431 is a wasteful number, since it uses less digits than its factorization.

28045431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3116165 (or 3116162 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 28045431 is about 5295.7937082179. The cubic root of 28045431 is about 303.8230409117.

The spelling of 28045431 in words is "twenty-eight million, forty-five thousand, four hundred thirty-one".