1321778288 has 20 divisors (see below), whose sum is σ = 2711589840. Its totient is φ = 622013184.

The previous prime is 1321778287. The next prime is 1321778291. The reversal of 1321778288 is 8828771231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321778287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2429468 + ... + 2430011.

It is an arithmetic number, because the mean of its divisors is an integer number (135579492).

Almost surely, 2^1321778288 is an apocalyptic number.

It is an amenable number.

1321778288 is an abundant number, since it is smaller than the sum of its proper divisors (1389811552).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1321778288 is a wasteful number, since it uses less digits than its factorization.

1321778288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4859504 (or 4859498 counting only the distinct ones).

The product of its digits is 301056, while the sum is 47.

The square root of 1321778288 is about 36356.2688954739. The cubic root of 1321778288 is about 1097.4536937687.

The spelling of 1321778288 in words is "one billion, three hundred twenty-one million, seven hundred seventy-eight thousand, two hundred eighty-eight".