66703909441 has 9 divisors (see below), whose sum is σ = 72233312931. Its totient is φ = 61569740232.

The previous prime is 66703909421. The next prime is 66703909451. The reversal of 66703909441 is 14490930766.

The square root of 66703909441 is 258271.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 9867442225 + 56836467216 = 99335^2 + 238404^2 .

It is not a de Polignac number, because 66703909441 - 2¹¹ = 66703907393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66703909411) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 3347590 + ... + 3367456.

It is an arithmetic number, because the mean of its divisors is an integer number (8025923659).

Almost surely, 2^66703909441 is an apocalyptic number.

66703909441 is the 258271-st square number.

66703909441 is the 129136-th centered octagonal number.

It is an amenable number.

66703909441 is a deficient number, since it is larger than the sum of its proper divisors (5529403490).

66703909441 is an frugal number, since it uses more digits than its factorization.

66703909441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39760 (or 19880 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 49.

Multiplying 66703909441 by its sum of digits (49), we get a square (3268491562609 = 1807897²).

It can be divided in two parts, 66703 and 909441, that added together give a square (976144 = 988²).

The spelling of 66703909441 in words is "sixty-six billion, seven hundred three million, nine hundred nine thousand, four hundred forty-one".