643154653 has 2 divisors, whose sum is σ = 643154654. Its totient is φ = 643154652.

The previous prime is 643154639. The next prime is 643154657. The reversal of 643154653 is 356451346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 535783609 + 107371044 = 23147^2 + 10362^2 .

It is a cyclic number.

It is not a de Polignac number, because 643154653 - 2¹³ = 643146461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643154657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321577326 + 321577327.

It is an arithmetic number, because the mean of its divisors is an integer number (321577327).

Almost surely, 2^643154653 is an apocalyptic number.

It is an amenable number.

643154653 is a deficient number, since it is larger than the sum of its proper divisors (1).

643154653 is an equidigital number, since it uses as much as digits as its factorization.

643154653 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 37.

The square root of 643154653 is about 25360.4939423506. The cubic root of 643154653 is about 863.1874921313.

The spelling of 643154653 in words is "six hundred forty-three million, one hundred fifty-four thousand, six hundred fifty-three".