212661944945 has 16 divisors (see below), whose sum is σ = 258828565968. Its totient is φ = 167720386560.

The previous prime is 212661944933. The next prime is 212661944953. The reversal of 212661944945 is 549449166212.

It can be written as a sum of positive squares in 8 ways, for example, as 22606926736 + 190055018209 = 150356^2 + 435953^2 .

It is not a de Polignac number, because 212661944945 - 2¹² = 212661940849 is a prime.

It is a super-2 number, since 2×212661944945² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 728426 + ... + 977715.

It is an arithmetic number, because the mean of its divisors is an integer number (16176785373).

Almost surely, 2^212661944945 is an apocalyptic number.

It is an amenable number.

212661944945 is a deficient number, since it is larger than the sum of its proper divisors (46166621023).

212661944945 is a wasteful number, since it uses less digits than its factorization.

212661944945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1706500.

The product of its digits is 3732480, while the sum is 53.

The spelling of 212661944945 in words is "two hundred twelve billion, six hundred sixty-one million, nine hundred forty-four thousand, nine hundred forty-five".