1649008640 has 112 divisors (see below), whose sum is σ = 4001121792. Its totient is φ = 652345344.

The previous prime is 1649008609. The next prime is 1649008693. The reversal of 1649008640 is 468009461.

It is a junction number, because it is equal to n+sod(n) for n = 1649008594 and 1649008603.

It is a congruent number.

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, 5201762 + ... + 5202078.

Almost surely, 2^1649008640 is an apocalyptic number.

1649008640 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 1649008640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2000560896).

1649008640 is an abundant number, since it is smaller than the sum of its proper divisors (2352113152).

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

1649008640 is an equidigital number, since it uses as much as digits as its factorization.

1649008640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475 (or 451 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 38.

The square root of 1649008640 is about 40607.9873916450. The cubic root of 1649008640 is about 1181.4290452453.

The spelling of 1649008640 in words is "one billion, six hundred forty-nine million, eight thousand, six hundred forty".