1144642640 has 80 divisors (see below), whose sum is σ = 2824493328. Its totient is φ = 429907968.

The previous prime is 1144642637. The next prime is 1144642649. The reversal of 1144642640 is 462464411.

It can be written as a sum of positive squares in 8 ways, for example, as 3013696 + 1141628944 = 1736^2 + 33788^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 1144642597 and 1144642606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1144642649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 832994 + ... + 834366.

Almost surely, 2^1144642640 is an apocalyptic number.

1144642640 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 1144642640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1412246664).

1144642640 is an abundant number, since it is smaller than the sum of its proper divisors (1679850688).

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

1144642640 is a wasteful number, since it uses less digits than its factorization.

1144642640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2016 (or 2010 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 1144642640 is about 33832.5677417485. The cubic root of 1144642640 is about 1046.0601071741.

The spelling of 1144642640 in words is "one billion, one hundred forty-four million, six hundred forty-two thousand, six hundred forty".