28321037 has 4 divisors (see below), whose sum is σ = 29011836. Its totient is φ = 27630240.

The previous prime is 28320979. The next prime is 28321061. The reversal of 28321037 is 73012382.

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 16801801 + 11519236 = 4099^2 + 3394^2 .

It is a cyclic number.

It is not a de Polignac number, because 28321037 - 2¹⁸ = 28058893 is a prime.

It is a super-2 number, since 2×28321037² = 1604162273510738, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28320997 and 28321015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28321537) 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, 345338 + ... + 345419.

It is an arithmetic number, because the mean of its divisors is an integer number (7252959).

Almost surely, 2^28321037 is an apocalyptic number.

It is an amenable number.

28321037 is a deficient number, since it is larger than the sum of its proper divisors (690799).

28321037 is an equidigital number, since it uses as much as digits as its factorization.

28321037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690798.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 28321037 is about 5321.7513094845. The cubic root of 28321037 is about 304.8150343172.

The spelling of 28321037 in words is "twenty-eight million, three hundred twenty-one thousand, thirty-seven".