1320972640 has 96 divisors (see below), whose sum is σ = 3381206976. Its totient is φ = 484792320.

The previous prime is 1320972623. The next prime is 1320972643. The reversal of 1320972640 is 462790231.

It is a junction number, because it is equal to n+sod(n) for n = 1320972596 and 1320972605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320972643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 358005 + ... + 361675.

It is an arithmetic number, because the mean of its divisors is an integer number (35220906).

Almost surely, 2^1320972640 is an apocalyptic number.

1320972640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1320972640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1690603488).

1320972640 is an abundant number, since it is smaller than the sum of its proper divisors (2060234336).

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

1320972640 is a wasteful number, since it uses less digits than its factorization.

1320972640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3872 (or 3864 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 1320972640 is about 36345.1873017598. The cubic root of 1320972640 is about 1097.2306757634.

It can be divided in two parts, 13209 and 72640, that added together give a square (85849 = 293²).

The spelling of 1320972640 in words is "one billion, three hundred twenty million, nine hundred seventy-two thousand, six hundred forty".