66198061 has 4 divisors (see below), whose sum is σ = 66995712. Its totient is φ = 65400412.

The previous prime is 66198053. The next prime is 66198073. The reversal of 66198061 is 16089166.

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 66198061 - 2³ = 66198053 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66198061.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66198031) 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, 398701 + ... + 398866.

It is an arithmetic number, because the mean of its divisors is an integer number (16748928).

Almost surely, 2^66198061 is an apocalyptic number.

It is an amenable number.

66198061 is a deficient number, since it is larger than the sum of its proper divisors (797651).

66198061 is an equidigital number, since it uses as much as digits as its factorization.

66198061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 797650.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 66198061 is about 8136.2190850542. The cubic root of 66198061 is about 404.5278468669.

The spelling of 66198061 in words is "sixty-six million, one hundred ninety-eight thousand, sixty-one".