1644045427 has 2 divisors, whose sum is σ = 1644045428. Its totient is φ = 1644045426.

The previous prime is 1644045419. The next prime is 1644045493. The reversal of 1644045427 is 7245404461.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1644045427 - 2³ = 1644045419 is a prime.

It is a super-3 number, since 3×1644045427³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (1644045407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822022713 + 822022714.

It is an arithmetic number, because the mean of its divisors is an integer number (822022714).

Almost surely, 2^1644045427 is an apocalyptic number.

1644045427 is a deficient number, since it is larger than the sum of its proper divisors (1).

1644045427 is an equidigital number, since it uses as much as digits as its factorization.

1644045427 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 107520, while the sum is 37.

The square root of 1644045427 is about 40546.8300487227. The cubic root of 1644045427 is about 1180.2425593004.

Adding to 1644045427 its reverse (7245404461), we get a palindrome (8889449888).

The spelling of 1644045427 in words is "one billion, six hundred forty-four million, forty-five thousand, four hundred twenty-seven".