66539716 has 6 divisors (see below), whose sum is σ = 116444510. Its totient is φ = 33269856.

The previous prime is 66539701. The next prime is 66539723. The reversal of 66539716 is 61793566.

It can be written as a sum of positive squares in only one way, i.e., 65674816 + 864900 = 8104^2 + 930^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8317461 + ... + 8317468.

Almost surely, 2^66539716 is an apocalyptic number.

It is an amenable number.

66539716 is a deficient number, since it is larger than the sum of its proper divisors (49904794).

66539716 is a wasteful number, since it uses less digits than its factorization.

66539716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16634933 (or 16634931 counting only the distinct ones).

The product of its digits is 204120, while the sum is 43.

The square root of 66539716 is about 8157.1879958721. The cubic root of 66539716 is about 405.2225896264. Note that the first 3 decimals are identical.

The spelling of 66539716 in words is "sixty-six million, five hundred thirty-nine thousand, seven hundred sixteen".