66277278061 has 4 divisors (see below), whose sum is σ = 66278101824. Its totient is φ = 66276454300.

The previous prime is 66277278047. The next prime is 66277278077. The reversal of 66277278061 is 16087277266.

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 66277278061 - 2¹⁹ = 66276753773 is a prime.

It is a super-2 number, since 2×66277278061² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66277278461) 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, 276325 + ... + 457066.

It is an arithmetic number, because the mean of its divisors is an integer number (16569525456).

Almost surely, 2^66277278061 is an apocalyptic number.

It is an amenable number.

66277278061 is a deficient number, since it is larger than the sum of its proper divisors (823763).

66277278061 is an equidigital number, since it uses as much as digits as its factorization.

66277278061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823762.

The product of its (nonzero) digits is 2370816, while the sum is 52.

The spelling of 66277278061 in words is "sixty-six billion, two hundred seventy-seven million, two hundred seventy-eight thousand, sixty-one".