66540704 has 36 divisors (see below), whose sum is σ = 134383662. Its totient is φ = 32432640.

The previous prime is 66540697. The next prime is 66540709. The reversal of 66540704 is 40704566.

It can be written as a sum of positive squares in 3 ways, for example, as 30780304 + 35760400 = 5548^2 + 5980^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (66540709) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 53174 + ... + 54410.

Almost surely, 2^66540704 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66540704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67191831).

66540704 is an abundant number, since it is smaller than the sum of its proper divisors (67842958).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66540704 is a wasteful number, since it uses less digits than its factorization.

66540704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1329 (or 1280 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 32.

The square root of 66540704 is about 8157.2485557325. The cubic root of 66540704 is about 405.2245952353.

The spelling of 66540704 in words is "sixty-six million, five hundred forty thousand, seven hundred four".