1643449599 has 48 divisors (see below), whose sum is σ = 2650021920. Its totient is φ = 972990720.

The previous prime is 1643449597. The next prime is 1643449603. The reversal of 1643449599 is 9959443461.

It is a happy number.

1643449599 is a `hidden beast` number, since 1 + 6 + 4 + 3 + 4 + 49 + 599 = 666.

It is not a de Polignac number, because 1643449599 - 2¹ = 1643449597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643449597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1536837 + ... + 1537905.

It is an arithmetic number, because the mean of its divisors is an integer number (55208790).

Almost surely, 2^1643449599 is an apocalyptic number.

1643449599 is a deficient number, since it is larger than the sum of its proper divisors (1006572321).

1643449599 is a wasteful number, since it uses less digits than its factorization.

1643449599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1432 (or 1429 counting only the distinct ones).

The product of its digits is 4199040, while the sum is 54.

The square root of 1643449599 is about 40539.4819774501. The cubic root of 1643449599 is about 1180.0999625648.

The spelling of 1643449599 in words is "one billion, six hundred forty-three million, four hundred forty-nine thousand, five hundred ninety-nine".