1643693453 has 2 divisors, whose sum is σ = 1643693454. Its totient is φ = 1643693452.

The previous prime is 1643693419. The next prime is 1643693461. The reversal of 1643693453 is 3543963461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 830188969 + 813504484 = 28813^2 + 28522^2 .

It is a cyclic number.

It is not a de Polignac number, because 1643693453 - 2¹⁶ = 1643627917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1643693473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821846726 + 821846727.

It is an arithmetic number, because the mean of its divisors is an integer number (821846727).

Almost surely, 2^1643693453 is an apocalyptic number.

It is an amenable number.

1643693453 is a deficient number, since it is larger than the sum of its proper divisors (1).

1643693453 is an equidigital number, since it uses as much as digits as its factorization.

1643693453 is an evil number, because the sum of its binary digits is even.

The product of its digits is 699840, while the sum is 44.

The square root of 1643693453 is about 40542.4894770906. The cubic root of 1643693453 is about 1180.1583271706.

The spelling of 1643693453 in words is "one billion, six hundred forty-three million, six hundred ninety-three thousand, four hundred fifty-three".