2661492678 has 64 divisors (see below), whose sum is σ = 6080659200. Its totient is φ = 769841280.

The previous prime is 2661492643. The next prime is 2661492689. The reversal of 2661492678 is 8762941662.

It is a super-2 number, since 2×2661492678² = 14167086550095223368, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2661492678.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 187288 + ... + 200996.

It is an arithmetic number, because the mean of its divisors is an integer number (95010300).

Almost surely, 2^2661492678 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2661492678, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3040329600).

2661492678 is an abundant number, since it is smaller than the sum of its proper divisors (3419166522).

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

2661492678 is a wasteful number, since it uses less digits than its factorization.

2661492678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13877.

The product of its digits is 1741824, while the sum is 51.

The square root of 2661492678 is about 51589.6566958921. The cubic root of 2661492678 is about 1385.8251071879.

The spelling of 2661492678 in words is "two billion, six hundred sixty-one million, four hundred ninety-two thousand, six hundred seventy-eight".