66605072 has 20 divisors (see below), whose sum is σ = 129721980. Its totient is φ = 33128448.

The previous prime is 66605059. The next prime is 66605117. The reversal of 66605072 is 27050666.

It can be written as a sum of positive squares in 2 ways, for example, as 7376656 + 59228416 = 2716^2 + 7696^2 .

It is a super-2 number, since 2×66605072² = 8872471232250368, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7697 + ... + 13872.

It is an arithmetic number, because the mean of its divisors is an integer number (6486099).

Almost surely, 2^66605072 is an apocalyptic number.

It is an amenable number.

66605072 is a deficient number, since it is larger than the sum of its proper divisors (63116908).

66605072 is a wasteful number, since it uses less digits than its factorization.

66605072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21770 (or 21764 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 66605072 is about 8161.1930500387. The cubic root of 66605072 is about 405.3552174915.

The spelling of 66605072 in words is "sixty-six million, six hundred five thousand, seventy-two".