212604139981 has 2 divisors, whose sum is σ = 212604139982. Its totient is φ = 212604139980.

The previous prime is 212604139927. The next prime is 212604140009. The reversal of 212604139981 is 189931406212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 184956764356 + 27647375625 = 430066^2 + 166275^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212604139981 is a prime.

It is a super-2 number, since 2×212604139981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212604139381) by changing a digit.

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 as a sum of consecutive naturals, namely, 106302069990 + 106302069991.

It is an arithmetic number, because the mean of its divisors is an integer number (106302069991).

Almost surely, 2^212604139981 is an apocalyptic number.

It is an amenable number.

212604139981 is a deficient number, since it is larger than the sum of its proper divisors (1).

212604139981 is an equidigital number, since it uses as much as digits as its factorization.

212604139981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 186624, while the sum is 46.

The spelling of 212604139981 in words is "two hundred twelve billion, six hundred four million, one hundred thirty-nine thousand, nine hundred eighty-one".