28439537 has 4 divisors (see below), whose sum is σ = 32502336. Its totient is φ = 24376740.

The previous prime is 28439533. The next prime is 28439573. The reversal of 28439537 is 73593482.

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: 73593482 = 2 ⋅36796741.

It is a cyclic number.

It is not a de Polignac number, because 28439537 - 2² = 28439533 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28439494 and 28439503.

It is not an unprimeable number, because it can be changed into a prime (28439531) 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, 2031389 + ... + 2031402.

It is an arithmetic number, because the mean of its divisors is an integer number (8125584).

Almost surely, 2^28439537 is an apocalyptic number.

It is an amenable number.

28439537 is a deficient number, since it is larger than the sum of its proper divisors (4062799).

28439537 is an equidigital number, since it uses as much as digits as its factorization.

28439537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4062798.

The product of its digits is 181440, while the sum is 41.

The square root of 28439537 is about 5332.8732405712. The cubic root of 28439537 is about 305.2395752705.

The spelling of 28439537 in words is "twenty-eight million, four hundred thirty-nine thousand, five hundred thirty-seven".