213121323009977 has 2 divisors, whose sum is σ = 213121323009978. Its totient is φ = 213121323009976.

The previous prime is 213121323009857. The next prime is 213121323010009. The reversal of 213121323009977 is 779900323121312.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 142926233190976 + 70195089819001 = 11955176^2 + 8378251^2 .

It is a cyclic number.

It is not a de Polignac number, because 213121323009977 - 2¹⁶ = 213121322944441 is a prime.

It is not a weakly prime, because it can be changed into another prime (213121323009377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106560661504988 + 106560661504989.

It is an arithmetic number, because the mean of its divisors is an integer number (106560661504989).

Almost surely, 2^{213121323009977} is an apocalyptic number.

It is an amenable number.

213121323009977 is a deficient number, since it is larger than the sum of its proper divisors (1).

213121323009977 is an equidigital number, since it uses as much as digits as its factorization.

213121323009977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 857304, while the sum is 50.

The spelling of 213121323009977 in words is "two hundred thirteen trillion, one hundred twenty-one billion, three hundred twenty-three million, nine thousand, nine hundred seventy-seven".