661272212 has 12 divisors (see below), whose sum is σ = 1157609460. Its totient is φ = 330526656.

The previous prime is 661272197. The next prime is 661272217. The reversal of 661272212 is 212272166.

It is a happy number.

661272212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 534349456 + 126922756 = 23116^2 + 11266^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661272217) 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, 12923 + ... + 38594.

It is an arithmetic number, because the mean of its divisors is an integer number (96467455).

Almost surely, 2^661272212 is an apocalyptic number.

It is an amenable number.

661272212 is a deficient number, since it is larger than the sum of its proper divisors (496337248).

661272212 is a wasteful number, since it uses less digits than its factorization.

661272212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54730 (or 54728 counting only the distinct ones).

The product of its digits is 4032, while the sum is 29.

The square root of 661272212 is about 25715.2136292896. The cubic root of 661272212 is about 871.2178355756.

The spelling of 661272212 in words is "six hundred sixty-one million, two hundred seventy-two thousand, two hundred twelve".