28172069 has 2 divisors, whose sum is σ = 28172070. Its totient is φ = 28172068.

The previous prime is 28172063. The next prime is 28172147. The reversal of 28172069 is 96027182.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15484225 + 12687844 = 3935^2 + 3562^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28172069 is a prime.

It is a super-2 number, since 2×28172069² = 1587330943481522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28172063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14086034 + 14086035.

It is an arithmetic number, because the mean of its divisors is an integer number (14086035).

Almost surely, 2^28172069 is an apocalyptic number.

It is an amenable number.

28172069 is a deficient number, since it is larger than the sum of its proper divisors (1).

28172069 is an equidigital number, since it uses as much as digits as its factorization.

28172069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 28172069 is about 5307.7367116314. The cubic root of 28172069 is about 304.2796545103.

The spelling of 28172069 in words is "twenty-eight million, one hundred seventy-two thousand, sixty-nine".