643442364451157 has 2 divisors, whose sum is σ = 643442364451158. Its totient is φ = 643442364451156.

The previous prime is 643442364451109. The next prime is 643442364451217. The reversal of 643442364451157 is 751154463244346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 354806423725636 + 288635940725521 = 18836306^2 + 16989289^2 .

It is a cyclic number.

It is not a de Polignac number, because 643442364451157 - 2¹⁸ = 643442364189013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 643442364451096 and 643442364451105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643441364451157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321721182225578 + 321721182225579.

It is an arithmetic number, because the mean of its divisors is an integer number (321721182225579).

Almost surely, 2^{643442364451157} is an apocalyptic number.

It is an amenable number.

643442364451157 is a deficient number, since it is larger than the sum of its proper divisors (1).

643442364451157 is an equidigital number, since it uses as much as digits as its factorization.

643442364451157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 116121600, while the sum is 59.

The spelling of 643442364451157 in words is "six hundred forty-three trillion, four hundred forty-two billion, three hundred sixty-four million, four hundred fifty-one thousand, one hundred fifty-seven".