28177997 has 2 divisors, whose sum is σ = 28177998. Its totient is φ = 28177996.

The previous prime is 28177991. The next prime is 28178009. The reversal of 28177997 is 79977182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28079401 + 98596 = 5299^2 + 314^2 .

It is a cyclic number.

It is not a de Polignac number, because 28177997 - 2²² = 23983693 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28177991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14088998 + 14088999.

It is an arithmetic number, because the mean of its divisors is an integer number (14088999).

Almost surely, 2^28177997 is an apocalyptic number.

It is an amenable number.

28177997 is a deficient number, since it is larger than the sum of its proper divisors (1).

28177997 is an equidigital number, since it uses as much as digits as its factorization.

28177997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 444528, while the sum is 50.

The square root of 28177997 is about 5308.2951123689. The cubic root of 28177997 is about 304.3009953082.

The spelling of 28177997 in words is "twenty-eight million, one hundred seventy-seven thousand, nine hundred ninety-seven".