2978782561 has 4 divisors (see below), whose sum is σ = 3027615124. Its totient is φ = 2929950000.

The previous prime is 2978782537. The next prime is 2978782607. The reversal of 2978782561 is 1652878792.

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 1300323600 + 1678458961 = 36060^2 + 40969^2 .

It is a cyclic number.

It is not a de Polignac number, because 2978782561 - 2¹¹ = 2978780513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2978782511) 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, 24416190 + ... + 24416311.

It is an arithmetic number, because the mean of its divisors is an integer number (756903781).

Almost surely, 2^2978782561 is an apocalyptic number.

It is an amenable number.

2978782561 is a deficient number, since it is larger than the sum of its proper divisors (48832563).

2978782561 is an equidigital number, since it uses as much as digits as its factorization.

2978782561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48832562.

The product of its digits is 3386880, while the sum is 55.

The square root of 2978782561 is about 54578.2242382436. The cubic root of 2978782561 is about 1438.8414293789.

The spelling of 2978782561 in words is "two billion, nine hundred seventy-eight million, seven hundred eighty-two thousand, five hundred sixty-one".