66796621 has 4 divisors (see below), whose sum is σ = 70725852. Its totient is φ = 62867392.

The previous prime is 66796619. The next prime is 66796627. The reversal of 66796621 is 12669766.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21031396 + 45765225 = 4586^2 + 6765^2 .

It is a cyclic number.

It is not a de Polignac number, because 66796621 - 2¹ = 66796619 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 (66796627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1964590 + ... + 1964623.

It is an arithmetic number, because the mean of its divisors is an integer number (17681463).

Almost surely, 2^66796621 is an apocalyptic number.

It is an amenable number.

66796621 is a deficient number, since it is larger than the sum of its proper divisors (3929231).

66796621 is a wasteful number, since it uses less digits than its factorization.

66796621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3929230.

The product of its digits is 163296, while the sum is 43.

The square root of 66796621 is about 8172.9199800316. The cubic root of 66796621 is about 405.7434315302.

The spelling of 66796621 in words is "sixty-six million, seven hundred ninety-six thousand, six hundred twenty-one".