28131069 has 4 divisors (see below), whose sum is σ = 37508096. Its totient is φ = 18754044.

The previous prime is 28131041. The next prime is 28131079. The reversal of 28131069 is 96013182.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28131069 - 2⁸ = 28130813 is a prime.

It is a super-2 number, since 2×28131069² = 1582714086165522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28131079) 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, 4688509 + ... + 4688514.

It is an arithmetic number, because the mean of its divisors is an integer number (9377024).

Almost surely, 2^28131069 is an apocalyptic number.

It is an amenable number.

28131069 is a deficient number, since it is larger than the sum of its proper divisors (9377027).

28131069 is an equidigital number, since it uses as much as digits as its factorization.

28131069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9377026.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 28131069 is about 5303.8730188420. The cubic root of 28131069 is about 304.1319725070.

The spelling of 28131069 in words is "twenty-eight million, one hundred thirty-one thousand, sixty-nine".