28971937 has 4 divisors (see below), whose sum is σ = 29102080. Its totient is φ = 28841796.

The previous prime is 28971931. The next prime is 28971947. The reversal of 28971937 is 73917982.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 73917982 = 2 ⋅36958991.

It is a cyclic number.

It is not a de Polignac number, because 28971937 - 2¹⁹ = 28447649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28971931) 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, 64737 + ... + 65182.

It is an arithmetic number, because the mean of its divisors is an integer number (7275520).

Almost surely, 2^28971937 is an apocalyptic number.

It is an amenable number.

28971937 is a deficient number, since it is larger than the sum of its proper divisors (130143).

28971937 is a wasteful number, since it uses less digits than its factorization.

28971937 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130142.

The product of its digits is 190512, while the sum is 46.

The square root of 28971937 is about 5382.5585923425. The cubic root of 28971937 is about 307.1325489445.

The spelling of 28971937 in words is "twenty-eight million, nine hundred seventy-one thousand, nine hundred thirty-seven".