2812957781 has 2 divisors, whose sum is σ = 2812957782. Its totient is φ = 2812957780.

The previous prime is 2812957769. The next prime is 2812957787. The reversal of 2812957781 is 1877592182.

2812957781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2773707556 + 39250225 = 52666^2 + 6265^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2812957781 is a prime.

It is a super-2 number, since 2×2812957781² = 15825462955376887922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2812957787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1406478890 + 1406478891.

It is an arithmetic number, because the mean of its divisors is an integer number (1406478891).

Almost surely, 2^2812957781 is an apocalyptic number.

It is an amenable number.

2812957781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2812957781 is an equidigital number, since it uses as much as digits as its factorization.

2812957781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 564480, while the sum is 50.

The square root of 2812957781 is about 53037.3244140388. The cubic root of 2812957781 is about 1411.6306237738.

The spelling of 2812957781 in words is "two billion, eight hundred twelve million, nine hundred fifty-seven thousand, seven hundred eighty-one".