1321444840 has 16 divisors (see below), whose sum is σ = 2973250980. Its totient is φ = 528577920.

The previous prime is 1321444837. The next prime is 1321444841. The reversal of 1321444840 is 484441231.

It can be written as a sum of positive squares in 2 ways, for example, as 1272919684 + 48525156 = 35678^2 + 6966^2 .

It is not an unprimeable number, because it can be changed into a prime (1321444841) 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, 16518021 + ... + 16518100.

Almost surely, 2^1321444840 is an apocalyptic number.

1321444840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321444840 is an abundant number, since it is smaller than the sum of its proper divisors (1651806140).

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

1321444840 is a wasteful number, since it uses less digits than its factorization.

1321444840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33036132 (or 33036128 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 31.

The square root of 1321444840 is about 36351.6827671017. The cubic root of 1321444840 is about 1097.3614002983.

The spelling of 1321444840 in words is "one billion, three hundred twenty-one million, four hundred forty-four thousand, eight hundred forty".