1331638944 has 48 divisors (see below), whose sum is σ = 3530187360. Its totient is φ = 439481600.

The previous prime is 1331638937. The next prime is 1331638961. The reversal of 1331638944 is 4498361331.

It is a tau number, because it is divible by the number of its divisors (48).

It is a junction number, because it is equal to n+sod(n) for n = 1331638896 and 1331638905.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58974 + ... + 78365.

It is an arithmetic number, because the mean of its divisors is an integer number (73545570).

Almost surely, 2^1331638944 is an apocalyptic number.

It is an amenable number.

1331638944 is an abundant number, since it is smaller than the sum of its proper divisors (2198548416).

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

1331638944 is a wasteful number, since it uses less digits than its factorization.

1331638944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137453 (or 137445 counting only the distinct ones).

The product of its digits is 186624, while the sum is 42.

The square root of 1331638944 is about 36491.6284098148. The cubic root of 1331638944 is about 1100.1759894727.

The spelling of 1331638944 in words is "one billion, three hundred thirty-one million, six hundred thirty-eight thousand, nine hundred forty-four".