669148261 has 2 divisors, whose sum is σ = 669148262. Its totient is φ = 669148260.

The previous prime is 669148247. The next prime is 669148279. The reversal of 669148261 is 162841966.

669148261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 462680100 + 206468161 = 21510^2 + 14369^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-669148261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669142261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334574130 + 334574131.

It is an arithmetic number, because the mean of its divisors is an integer number (334574131).

Almost surely, 2^669148261 is an apocalyptic number.

It is an amenable number.

669148261 is a deficient number, since it is larger than the sum of its proper divisors (1).

669148261 is an equidigital number, since it uses as much as digits as its factorization.

669148261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 124416, while the sum is 43.

The square root of 669148261 is about 25867.9002046938. The cubic root of 669148261 is about 874.6630587313.

The spelling of 669148261 in words is "six hundred sixty-nine million, one hundred forty-eight thousand, two hundred sixty-one".