2493660781 has 4 divisors (see below), whose sum is σ = 2496938364. Its totient is φ = 2490383200.

The previous prime is 2493660751. The next prime is 2493660821. The reversal of 2493660781 is 1870663942.

2493660781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 906913225 + 1586747556 = 30115^2 + 39834^2 .

It is a cyclic number.

It is not a de Polignac number, because 2493660781 - 2⁹ = 2493660269 is a prime.

It is a super-2 number, since 2×2493660781² = 12436688181395059922, 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 (2493660751) 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, 1637650 + ... + 1639171.

It is an arithmetic number, because the mean of its divisors is an integer number (624234591).

Almost surely, 2^2493660781 is an apocalyptic number.

It is an amenable number.

2493660781 is a deficient number, since it is larger than the sum of its proper divisors (3277583).

2493660781 is an equidigital number, since it uses as much as digits as its factorization.

2493660781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3277582.

The product of its (nonzero) digits is 435456, while the sum is 46.

The square root of 2493660781 is about 49936.5675732724. The cubic root of 2493660781 is about 1356.0606848072.

The spelling of 2493660781 in words is "two billion, four hundred ninety-three million, six hundred sixty thousand, seven hundred eighty-one".