2774400781 has 2 divisors, whose sum is σ = 2774400782. Its totient is φ = 2774400780.

The previous prime is 2774400779. The next prime is 2774400787. The reversal of 2774400781 is 1870044772.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2104056900 + 670343881 = 45870^2 + 25891^2 .

It is a cyclic number.

It is not a de Polignac number, because 2774400781 - 2¹ = 2774400779 is a prime.

It is a super-2 number, since 2×2774400781² = 15394599387226819922, which contains 22 as substring.

Together with 2774400779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2774400787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1387200390 + 1387200391.

It is an arithmetic number, because the mean of its divisors is an integer number (1387200391).

Almost surely, 2^2774400781 is an apocalyptic number.

It is an amenable number.

2774400781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2774400781 is an equidigital number, since it uses as much as digits as its factorization.

2774400781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 87808, while the sum is 40.

The square root of 2774400781 is about 52672.5809221458. The cubic root of 2774400781 is about 1405.1512239553.

The spelling of 2774400781 in words is "two billion, seven hundred seventy-four million, four hundred thousand, seven hundred eighty-one".