1287665373 has 16 divisors (see below), whose sum is σ = 1792400256. Its totient is φ = 820723200.

The previous prime is 1287665317. The next prime is 1287665389. The reversal of 1287665373 is 3735667821.

It is not a de Polignac number, because 1287665373 - 2⁸ = 1287665117 is a prime.

It is a super-2 number, since 2×1287665373² = 3316164225646458258, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287665303) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 219073 + ... + 224873.

It is an arithmetic number, because the mean of its divisors is an integer number (112025016).

Almost surely, 2^1287665373 is an apocalyptic number.

It is an amenable number.

1287665373 is a deficient number, since it is larger than the sum of its proper divisors (504734883).

1287665373 is a wasteful number, since it uses less digits than its factorization.

1287665373 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9044.

The product of its digits is 1270080, while the sum is 48.

The square root of 1287665373 is about 35884.0545786008. The cubic root of 1287665373 is about 1087.9301327166.

The spelling of 1287665373 in words is "one billion, two hundred eighty-seven million, six hundred sixty-five thousand, three hundred seventy-three".