1287224405 has 4 divisors (see below), whose sum is σ = 1544669292. Its totient is φ = 1029779520.

The previous prime is 1287224401. The next prime is 1287224423. The reversal of 1287224405 is 5044227821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5044227821 = 15737 ⋅320533.

It can be written as a sum of positive squares in 2 ways, for example, as 131836324 + 1155388081 = 11482^2 + 33991^2 .

It is not a de Polignac number, because 1287224405 - 2² = 1287224401 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 (1287224401) 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 in 3 ways as a sum of consecutive naturals, for example, 128722436 + ... + 128722445.

It is an arithmetic number, because the mean of its divisors is an integer number (386167323).

Almost surely, 2^1287224405 is an apocalyptic number.

It is an amenable number.

1287224405 is a deficient number, since it is larger than the sum of its proper divisors (257444887).

1287224405 is an equidigital number, since it uses as much as digits as its factorization.

1287224405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257444886.

The product of its (nonzero) digits is 35840, while the sum is 35.

The square root of 1287224405 is about 35877.9097077854. The cubic root of 1287224405 is about 1087.8059293434.

The spelling of 1287224405 in words is "one billion, two hundred eighty-seven million, two hundred twenty-four thousand, four hundred five".