28237961 has 4 divisors (see below), whose sum is σ = 28529172. Its totient is φ = 27946752.

The previous prime is 28237949. The next prime is 28237981. The reversal of 28237961 is 16973282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16973282 = 2 ⋅8486641.

It can be written as a sum of positive squares in 2 ways, for example, as 7590025 + 20647936 = 2755^2 + 4544^2 .

It is a cyclic number.

It is not a de Polignac number, because 28237961 - 2⁶ = 28237897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28237981) 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, 145460 + ... + 145653.

It is an arithmetic number, because the mean of its divisors is an integer number (7132293).

Almost surely, 2^28237961 is an apocalyptic number.

It is an amenable number.

28237961 is a deficient number, since it is larger than the sum of its proper divisors (291211).

28237961 is an equidigital number, since it uses as much as digits as its factorization.

28237961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291210.

The product of its digits is 36288, while the sum is 38.

The square root of 28237961 is about 5313.9402518282. The cubic root of 28237961 is about 304.5166976121.

The spelling of 28237961 in words is "twenty-eight million, two hundred thirty-seven thousand, nine hundred sixty-one".