281616997 has 4 divisors (see below), whose sum is σ = 287608896. Its totient is φ = 275625100.

The previous prime is 281616949. The next prime is 281617073. The reversal of 281616997 is 799616182.

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 281616997 - 2¹⁹ = 281092709 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 281616997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281616947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2995879 + ... + 2995972.

It is an arithmetic number, because the mean of its divisors is an integer number (71902224).

Almost surely, 2^281616997 is an apocalyptic number.

It is an amenable number.

281616997 is a deficient number, since it is larger than the sum of its proper divisors (5991899).

281616997 is an equidigital number, since it uses as much as digits as its factorization.

281616997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5991898.

The product of its digits is 326592, while the sum is 49.

The square root of 281616997 is about 16781.4480006941. The cubic root of 281616997 is about 655.4702037186.

The spelling of 281616997 in words is "two hundred eighty-one million, six hundred sixteen thousand, nine hundred ninety-seven".