65643530 has 16 divisors (see below), whose sum is σ = 122233320. Its totient is φ = 25351872.

The previous prime is 65643497. The next prime is 65643551. The reversal of 65643530 is 3534656.

It can be written as a sum of positive squares in 4 ways, for example, as 64272289 + 1371241 = 8017^2 + 1171^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112889 + ... + 113468.

Almost surely, 2^65643530 is an apocalyptic number.

65643530 is a deficient number, since it is larger than the sum of its proper divisors (56589790).

65643530 is a wasteful number, since it uses less digits than its factorization.

65643530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226393.

The product of its (nonzero) digits is 32400, while the sum is 32.

The square root of 65643530 is about 8102.0694887171. The cubic root of 65643530 is about 403.3951221656.

The spelling of 65643530 in words is "sixty-five million, six hundred forty-three thousand, five hundred thirty".