66912061 has 4 divisors (see below), whose sum is σ = 66960000. Its totient is φ = 66864124.

The previous prime is 66912031. The next prime is 66912089. The reversal of 66912061 is 16021966.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66912061 - 2¹³ = 66903869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66912011) 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, 21811 + ... + 24688.

It is an arithmetic number, because the mean of its divisors is an integer number (16740000).

Almost surely, 2^66912061 is an apocalyptic number.

It is an amenable number.

66912061 is a deficient number, since it is larger than the sum of its proper divisors (47939).

66912061 is a wasteful number, since it uses less digits than its factorization.

66912061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47938.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 66912061 is about 8179.9792787024. The cubic root of 66912061 is about 405.9770364842.

The spelling of 66912061 in words is "sixty-six million, nine hundred twelve thousand, sixty-one".