1290864321 has 6 divisors (see below), whose sum is σ = 1864581810. Its totient is φ = 860576208.

The previous prime is 1290864317. The next prime is 1290864347. The reversal of 1290864321 is 1234680921.

1290864321 is a `hidden beast` number, since 1 + 2 + 9 + 0 + 8 + 643 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 825987600 + 464876721 = 28740^2 + 21561^2 .

It is not a de Polignac number, because 1290864321 - 2² = 1290864317 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1290864361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 71714676 + ... + 71714693.

It is an arithmetic number, because the mean of its divisors is an integer number (310763635).

Almost surely, 2^1290864321 is an apocalyptic number.

It is an amenable number.

1290864321 is a deficient number, since it is larger than the sum of its proper divisors (573717489).

1290864321 is a wasteful number, since it uses less digits than its factorization.

1290864321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143429375 (or 143429372 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 1290864321 is about 35928.6003206359. The cubic root of 1290864321 is about 1088.8303028967.

The spelling of 1290864321 in words is "one billion, two hundred ninety million, eight hundred sixty-four thousand, three hundred twenty-one".