28138671 has 56 divisors (see below), whose sum is σ = 48004560. Its totient is φ = 16465680.

The previous prime is 28138667. The next prime is 28138679. The reversal of 28138671 is 17683182.

It is not a de Polignac number, because 28138671 - 2² = 28138667 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28138679) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 970285 + ... + 970313.

Almost surely, 2^28138671 is an apocalyptic number.

28138671 is a deficient number, since it is larger than the sum of its proper divisors (19865889).

28138671 is an frugal number, since it uses more digits than its factorization.

28138671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80 (or 43 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 28138671 is about 5304.5896165491. The cubic root of 28138671 is about 304.1593657429.

The spelling of 28138671 in words is "twenty-eight million, one hundred thirty-eight thousand, six hundred seventy-one".