1288805380 has 12 divisors (see below), whose sum is σ = 2706491340. Its totient is φ = 515522144.

The previous prime is 1288805339. The next prime is 1288805389. The reversal of 1288805380 is 835088821.

It can be written as a sum of positive squares in 2 ways, for example, as 358799364 + 930006016 = 18942^2 + 30496^2 .

It is a super-2 number, since 2×1288805380² = 3322038615033888800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1288805389) 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, 32220115 + ... + 32220154.

It is an arithmetic number, because the mean of its divisors is an integer number (225540945).

Almost surely, 2^1288805380 is an apocalyptic number.

1288805380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1288805380 is an abundant number, since it is smaller than the sum of its proper divisors (1417685960).

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

1288805380 is a wasteful number, since it uses less digits than its factorization.

1288805380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64440278 (or 64440276 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 43.

The square root of 1288805380 is about 35899.9356545384. The cubic root of 1288805380 is about 1088.2510965746.

The spelling of 1288805380 in words is "one billion, two hundred eighty-eight million, eight hundred five thousand, three hundred eighty".