6649709418 has 80 divisors (see below), whose sum is σ = 16399190016. Its totient is φ = 1997170560.

The previous prime is 6649709411. The next prime is 6649709447. The reversal of 6649709418 is 8149079466.

6649709418 is a `hidden beast` number, since 66 + 497 + 0 + 94 + 1 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6649709411) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 184855 + ... + 217877.

Almost surely, 2^6649709418 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6649709418, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8199595008).

6649709418 is an abundant number, since it is smaller than the sum of its proper divisors (9749480598).

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

6649709418 is a wasteful number, since it uses less digits than its factorization.

6649709418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33161 (or 33152 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The square root of 6649709418 is about 81545.7504594813. The cubic root of 6649709418 is about 1880.4749646859.

The spelling of 6649709418 in words is "six billion, six hundred forty-nine million, seven hundred nine thousand, four hundred eighteen".