6649955739648 has 480 divisors, whose sum is σ = 21969229562280. Its totient is φ = 1990815252480.

The previous prime is 6649955739571. The next prime is 6649955739667. The reversal of 6649955739648 is 8469375599466.

6649955739648 is a `hidden beast` number, since 6 + 6 + 499 + 5 + 57 + 39 + 6 + 48 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 6541972521984 + 107983217664 = 2557728^2 + 328608^2 .

It is a super-2 number, since 2×6649955739648² (a number of 26 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 79750458 + ... + 79833798.

Almost surely, 2^{6649955739648} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6649955739648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10984614781140).

6649955739648 is an abundant number, since it is smaller than the sum of its proper divisors (15319273822632).

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

6649955739648 is a wasteful number, since it uses less digits than its factorization.

6649955739648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83425 (or 83396 counting only the distinct ones).

The product of its digits is 10581580800, while the sum is 81.

The spelling of 6649955739648 in words is "six trillion, six hundred forty-nine billion, nine hundred fifty-five million, seven hundred thirty-nine thousand, six hundred forty-eight".