643523141 has 32 divisors (see below), whose sum is σ = 741580800. Its totient is φ = 555128640.

The previous prime is 643523131. The next prime is 643523143. The reversal of 643523141 is 141325346.

It is a cyclic number.

It is not a de Polignac number, because 643523141 - 2¹⁸ = 643260997 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 (643523143) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 907295 + ... + 908003.

It is an arithmetic number, because the mean of its divisors is an integer number (23174400).

Almost surely, 2^643523141 is an apocalyptic number.

It is an amenable number.

643523141 is a deficient number, since it is larger than the sum of its proper divisors (98057659).

643523141 is a wasteful number, since it uses less digits than its factorization.

643523141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 849.

The product of its digits is 8640, while the sum is 29.

The square root of 643523141 is about 25367.7579025029. The cubic root of 643523141 is about 863.3523117460.

Adding to 643523141 its reverse (141325346), we get a palindrome (784848487).

The spelling of 643523141 in words is "six hundred forty-three million, five hundred twenty-three thousand, one hundred forty-one".