281688131 has 2 divisors, whose sum is σ = 281688132. Its totient is φ = 281688130.

The previous prime is 281688119. The next prime is 281688151. The reversal of 281688131 is 131886182.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 281688131 - 2¹⁸ = 281425987 is a prime.

It is a super-2 number, since 2×281688131² = 158696406292546322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (281688151) 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 as a sum of consecutive naturals, namely, 140844065 + 140844066.

It is an arithmetic number, because the mean of its divisors is an integer number (140844066).

Almost surely, 2^281688131 is an apocalyptic number.

281688131 is a deficient number, since it is larger than the sum of its proper divisors (1).

281688131 is an equidigital number, since it uses as much as digits as its factorization.

281688131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18432, while the sum is 38.

The square root of 281688131 is about 16783.5672906567. The cubic root of 281688131 is about 655.5253877602.

The spelling of 281688131 in words is "two hundred eighty-one million, six hundred eighty-eight thousand, one hundred thirty-one".