2128426649 has 2 divisors, whose sum is σ = 2128426650. Its totient is φ = 2128426648.

The previous prime is 2128426633. The next prime is 2128426661. The reversal of 2128426649 is 9466248212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2128161424 + 265225 = 46132^2 + 515^2 .

It is a cyclic number.

It is not a de Polignac number, because 2128426649 - 2⁴ = 2128426633 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (2128426679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1064213324 + 1064213325.

It is an arithmetic number, because the mean of its divisors is an integer number (1064213325).

Almost surely, 2^2128426649 is an apocalyptic number.

It is an amenable number.

2128426649 is a deficient number, since it is larger than the sum of its proper divisors (1).

2128426649 is an equidigital number, since it uses as much as digits as its factorization.

2128426649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 331776, while the sum is 44.

The square root of 2128426649 is about 46134.8745419341. The cubic root of 2128426649 is about 1286.3314735850.

The spelling of 2128426649 in words is "two billion, one hundred twenty-eight million, four hundred twenty-six thousand, six hundred forty-nine".