66712061 has 4 divisors (see below), whose sum is σ = 71843772. Its totient is φ = 61580352.

The previous prime is 66712027. The next prime is 66712091. The reversal of 66712061 is 16021766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16021766 = 2 ⋅8010883.

It can be written as a sum of positive squares in 2 ways, for example, as 30591961 + 36120100 = 5531^2 + 6010^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66712061 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66712091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2565836 + ... + 2565861.

It is an arithmetic number, because the mean of its divisors is an integer number (17960943).

Almost surely, 2^66712061 is an apocalyptic number.

It is an amenable number.

66712061 is a deficient number, since it is larger than the sum of its proper divisors (5131711).

66712061 is a wasteful number, since it uses less digits than its factorization.

66712061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5131710.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 66712061 is about 8167.7451600794. The cubic root of 66712061 is about 405.5721446590.

The spelling of 66712061 in words is "sixty-six million, seven hundred twelve thousand, sixty-one".