2780749399 has 2 divisors, whose sum is σ = 2780749400. Its totient is φ = 2780749398.

The previous prime is 2780749373. The next prime is 2780749421. The reversal of 2780749399 is 9939470872.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2780749399 is a prime.

It is a super-2 number, since 2×2780749399² = 15465134440077722402, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2780749369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1390374699 + 1390374700.

It is an arithmetic number, because the mean of its divisors is an integer number (1390374700).

Almost surely, 2^2780749399 is an apocalyptic number.

2780749399 is a deficient number, since it is larger than the sum of its proper divisors (1).

2780749399 is an equidigital number, since it uses as much as digits as its factorization.

2780749399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6858432, while the sum is 58.

The square root of 2780749399 is about 52732.8114080787. The cubic root of 2780749399 is about 1406.2222026729. Note that the first 4 decimals are identical.

The spelling of 2780749399 in words is "two billion, seven hundred eighty million, seven hundred forty-nine thousand, three hundred ninety-nine".