28253131 has 4 divisors (see below), whose sum is σ = 29481552. Its totient is φ = 27024712.

The previous prime is 28253119. The next prime is 28253143. The reversal of 28253131 is 13135282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13135282 = 2 ⋅6567641.

It is an interprime number because it is at equal distance from previous prime (28253119) and next prime (28253143).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28253131 is a prime.

It is a super-2 number, since 2×28253131² = 1596478822606322, 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 = 28253096 and 28253105.

It is not an unprimeable number, because it can be changed into a prime (28253161) 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, 614176 + ... + 614221.

It is an arithmetic number, because the mean of its divisors is an integer number (7370388).

Almost surely, 2^28253131 is an apocalyptic number.

28253131 is a deficient number, since it is larger than the sum of its proper divisors (1228421).

28253131 is a wasteful number, since it uses less digits than its factorization.

28253131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1228420.

The product of its digits is 1440, while the sum is 25.

The square root of 28253131 is about 5315.3674379106. The cubic root of 28253131 is about 304.5712186794.

The spelling of 28253131 in words is "twenty-eight million, two hundred fifty-three thousand, one hundred thirty-one".