212020018953661 has 2 divisors, whose sum is σ = 212020018953662. Its totient is φ = 212020018953660.

The previous prime is 212020018953641. The next prime is 212020018953683. The reversal of 212020018953661 is 166359810020212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 141295871598436 + 70724147355225 = 11886794^2 + 8409765^2 .

It is a cyclic number.

It is not a de Polignac number, because 212020018953661 - 2¹¹ = 212020018951613 is a prime.

It is a super-2 number, since 2×212020018953661² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212020018953641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106010009476830 + 106010009476831.

It is an arithmetic number, because the mean of its divisors is an integer number (106010009476831).

Almost surely, 2^{212020018953661} is an apocalyptic number.

It is an amenable number.

212020018953661 is a deficient number, since it is larger than the sum of its proper divisors (1).

212020018953661 is an equidigital number, since it uses as much as digits as its factorization.

212020018953661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 311040, while the sum is 46.

Adding to 212020018953661 its reverse (166359810020212), we get a palindrome (378379828973873).

The spelling of 212020018953661 in words is "two hundred twelve trillion, twenty billion, eighteen million, nine hundred fifty-three thousand, six hundred sixty-one".