1643729453 has 8 divisors (see below), whose sum is σ = 1655400000. Its totient is φ = 1632093408.

The previous prime is 1643729419. The next prime is 1643729459. The reversal of 1643729453 is 3549273461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1643729453 - 2⁶ = 1643729389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643729459) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91025 + ... + 107577.

It is an arithmetic number, because the mean of its divisors is an integer number (206925000).

Almost surely, 2^1643729453 is an apocalyptic number.

It is an amenable number.

1643729453 is a deficient number, since it is larger than the sum of its proper divisors (11670547).

1643729453 is a wasteful number, since it uses less digits than its factorization.

1643729453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17251.

The product of its digits is 544320, while the sum is 44.

The square root of 1643729453 is about 40542.9334533159. The cubic root of 1643729453 is about 1180.1669430086.

The spelling of 1643729453 in words is "one billion, six hundred forty-three million, seven hundred twenty-nine thousand, four hundred fifty-three".