1440728640 has 448 divisors, whose sum is σ = 5571256320. Its totient is φ = 348364800.

The previous prime is 1440728623. The next prime is 1440728651. The reversal of 1440728640 is 468270441.

1440728640 is a `hidden beast` number, since 1 + 4 + 4 + 0 + 7 + 2 + 8 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1440728595 and 1440728604.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11344257 + ... + 11344383.

It is an arithmetic number, because the mean of its divisors is an integer number (12435840).

Almost surely, 2^1440728640 is an apocalyptic number.

1440728640 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 1440728640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2785628160).

1440728640 is an abundant number, since it is smaller than the sum of its proper divisors (4130527680).

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

1440728640 is a wasteful number, since it uses less digits than its factorization.

1440728640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267 (or 251 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The square root of 1440728640 is about 37956.9313828186. The cubic root of 1440728640 is about 1129.4336682333.

The spelling of 1440728640 in words is "one billion, four hundred forty million, seven hundred twenty-eight thousand, six hundred forty".