2748066781 has 4 divisors (see below), whose sum is σ = 2748483100.
Its totient is φ = 2747650464.
The previous prime is 2748066751. The next prime is 2748066787. The reversal of 2748066781 is 1876608472.
It is a happy number.
It is a semiprime because it is the product of two primes.
It can be written as a sum of positive squares in 2 ways, for example, as 2484524025 + 263542756 = 49845^2 + 16234^2
It is a cyclic number.
It is not a de Polignac number, because 2748066781 - 215 = 2748034013 is a prime.
It is a super-2 number, since 2×27480667812 = 15103742065671403922, which contains 22 as substring.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (2748066787) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198096 + ... + 211513.
It is an arithmetic number, because the mean of its divisors is an integer number (687120775).
Almost surely, 22748066781 is an apocalyptic number.
It is an amenable number.
2748066781 is a deficient number, since it is larger than the sum of its proper divisors (416319).
2748066781 is an equidigital number, since it uses as much as digits as its factorization.
2748066781 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 416318.
The product of its (nonzero) digits is 903168, while the sum is 49.
The square root of 2748066781 is about 52422.0066479718.
The cubic root of 2748066781 is about 1400.6912880233.
The spelling of 2748066781 in words is "two billion, seven hundred forty-eight million, sixty-six thousand, seven hundred eighty-one".