66121722 has 12 divisors (see below), whose sum is σ = 143263770. Its totient is φ = 22040568.

The previous prime is 66121681. The next prime is 66121733. The reversal of 66121722 is 22712166.

It can be written as a sum of positive squares in only one way, i.e., 55487601 + 10634121 = 7449^2 + 3261^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1836697 + ... + 1836732.

Almost surely, 2^66121722 is an apocalyptic number.

66121722 is an abundant number, since it is smaller than the sum of its proper divisors (77142048).

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

66121722 is a wasteful number, since it uses less digits than its factorization.

66121722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3673437 (or 3673434 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 66121722 is about 8131.5264249709. The cubic root of 66121722 is about 404.3722877810.

Adding to 66121722 its reverse (22712166), we get a palindrome (88833888).

The spelling of 66121722 in words is "sixty-six million, one hundred twenty-one thousand, seven hundred twenty-two".