281312639 has 2 divisors, whose sum is σ = 281312640. Its totient is φ = 281312638.

The previous prime is 281312627. The next prime is 281312683. The reversal of 281312639 is 936213182.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 281312639 - 2¹² = 281308543 is a prime.

It is a super-2 number, since 2×281312639² = 158273601722288642, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 281312599 and 281312608.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (283312639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140656319 + 140656320.

It is an arithmetic number, because the mean of its divisors is an integer number (140656320).

Almost surely, 2^281312639 is an apocalyptic number.

281312639 is a deficient number, since it is larger than the sum of its proper divisors (1).

281312639 is an equidigital number, since it uses as much as digits as its factorization.

281312639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 35.

The square root of 281312639 is about 16772.3772614379. The cubic root of 281312639 is about 655.2339851254.

The spelling of 281312639 in words is "two hundred eighty-one million, three hundred twelve thousand, six hundred thirty-nine".