1320139644 has 24 divisors (see below), whose sum is σ = 3091699968. Its totient is φ = 438421680.

The previous prime is 1320139643. The next prime is 1320139661. The reversal of 1320139644 is 4469310231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320139643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 199722 + ... + 206225.

It is an arithmetic number, because the mean of its divisors is an integer number (128820832).

Almost surely, 2^1320139644 is an apocalyptic number.

It is an amenable number.

1320139644 is an abundant number, since it is smaller than the sum of its proper divisors (1771560324).

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

1320139644 is a wasteful number, since it uses less digits than its factorization.

1320139644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406225 (or 406223 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 1320139644 is about 36333.7259856459. The cubic root of 1320139644 is about 1096.9999919673. Note that the first 5 decimals are identical.

Adding to 1320139644 its reverse (4469310231), we get a palindrome (5789449875).

The spelling of 1320139644 in words is "one billion, three hundred twenty million, one hundred thirty-nine thousand, six hundred forty-four".