643053637 has 2 divisors, whose sum is σ = 643053638. Its totient is φ = 643053636.

The previous prime is 643053623. The next prime is 643053641. The reversal of 643053637 is 736350346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 388523521 + 254530116 = 19711^2 + 15954^2 .

It is a cyclic number.

It is not a de Polignac number, because 643053637 - 2²⁷ = 508835909 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 643053596 and 643053605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643053647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321526818 + 321526819.

It is an arithmetic number, because the mean of its divisors is an integer number (321526819).

Almost surely, 2^643053637 is an apocalyptic number.

It is an amenable number.

643053637 is a deficient number, since it is larger than the sum of its proper divisors (1).

643053637 is an equidigital number, since it uses as much as digits as its factorization.

643053637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 136080, while the sum is 37.

The square root of 643053637 is about 25358.5022625549. The cubic root of 643053637 is about 863.1422980697.

The spelling of 643053637 in words is "six hundred forty-three million, fifty-three thousand, six hundred thirty-seven".