281238013 has 4 divisors (see below), whose sum is σ = 321414880. Its totient is φ = 241061148.

The previous prime is 281237977. The next prime is 281238037. The reversal of 281238013 is 310832182.

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.

It is a cyclic number.

It is not a de Polignac number, because 281238013 - 2²¹ = 279140861 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 (281238613) 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, 20088423 + ... + 20088436.

It is an arithmetic number, because the mean of its divisors is an integer number (80353720).

Almost surely, 2^281238013 is an apocalyptic number.

It is an amenable number.

281238013 is a deficient number, since it is larger than the sum of its proper divisors (40176867).

281238013 is an equidigital number, since it uses as much as digits as its factorization.

281238013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40176866.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 281238013 is about 16770.1524441491. The cubic root of 281238013 is about 655.1760403231.

The spelling of 281238013 in words is "two hundred eighty-one million, two hundred thirty-eight thousand, thirteen".