28671397 has 4 divisors (see below), whose sum is σ = 28753900. Its totient is φ = 28588896.

The previous prime is 28671353. The next prime is 28671421. The reversal of 28671397 is 79317682.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13060996 + 15610401 = 3614^2 + 3951^2 .

It is a cyclic number.

It is not a de Polignac number, because 28671397 - 2¹⁹ = 28147109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28671347) 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, 40728 + ... + 41425.

It is an arithmetic number, because the mean of its divisors is an integer number (7188475).

Almost surely, 2^28671397 is an apocalyptic number.

It is an amenable number.

28671397 is a deficient number, since it is larger than the sum of its proper divisors (82503).

28671397 is an equidigital number, since it uses as much as digits as its factorization.

28671397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82502.

The product of its digits is 127008, while the sum is 43.

The square root of 28671397 is about 5354.5678630493. The cubic root of 28671397 is about 306.0668435859.

The spelling of 28671397 in words is "twenty-eight million, six hundred seventy-one thousand, three hundred ninety-seven".