28023631 has 4 divisors (see below), whose sum is σ = 28034872. Its totient is φ = 28012392.

The previous prime is 28023617. The next prime is 28023647. The reversal of 28023631 is 13632082.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 28023631 - 2⁷ = 28023503 is a prime.

It is a super-2 number, since 2×28023631² = 1570647788848322, 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 = 28023596 and 28023605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28023691) 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, 21 + ... + 7486.

It is an arithmetic number, because the mean of its divisors is an integer number (7008718).

Almost surely, 2^28023631 is an apocalyptic number.

28023631 is a deficient number, since it is larger than the sum of its proper divisors (11241).

28023631 is an equidigital number, since it uses as much as digits as its factorization.

28023631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11240.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 28023631 is about 5293.7350708172. The cubic root of 28023631 is about 303.7442989215.

The spelling of 28023631 in words is "twenty-eight million, twenty-three thousand, six hundred thirty-one".