6649138692 has 480 divisors, whose sum is σ = 22116864000. Its totient is φ = 1735183296.

The previous prime is 6649138679. The next prime is 6649138723. The reversal of 6649138692 is 2968319466.

6649138692 is a `hidden beast` number, since 66 + 491 + 3 + 8 + 6 + 92 = 666.

It is a super-2 number, since 2×6649138692² = 88422090690902941728, which contains 22 as substring.

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

It is an unprimeable number.

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 159 ways as a sum of consecutive naturals, for example, 99240843 + ... + 99240909.

It is an arithmetic number, because the mean of its divisors is an integer number (46076800).

Almost surely, 2^6649138692 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 6649138692, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11058432000).

6649138692 is an abundant number, since it is smaller than the sum of its proper divisors (15467725308).

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

6649138692 is a wasteful number, since it uses less digits than its factorization.

6649138692 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170 (or 145 counting only the distinct ones).

The product of its digits is 3359232, while the sum is 54.

The square root of 6649138692 is about 81542.2509623079. The cubic root of 6649138692 is about 1880.4211645074.

The spelling of 6649138692 in words is "six billion, six hundred forty-nine million, one hundred thirty-eight thousand, six hundred ninety-two".