205414152421 has 2 divisors, whose sum is σ = 205414152422. Its totient is φ = 205414152420.

The previous prime is 205414152409. The next prime is 205414152443. The reversal of 205414152421 is 124251414502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 187303721796 + 18110430625 = 432786^2 + 134575^2 .

It is a cyclic number.

It is not a de Polignac number, because 205414152421 - 2²⁹ = 204877281509 is a prime.

It is a super-2 number, since 2×205414152421² (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 (205414150421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102707076210 + 102707076211.

It is an arithmetic number, because the mean of its divisors is an integer number (102707076211).

Almost surely, 2^205414152421 is an apocalyptic number.

It is an amenable number.

205414152421 is a deficient number, since it is larger than the sum of its proper divisors (1).

205414152421 is an equidigital number, since it uses as much as digits as its factorization.

205414152421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12800, while the sum is 31.

Adding to 205414152421 its reverse (124251414502), we get a palindrome (329665566923).

The spelling of 205414152421 in words is "two hundred five billion, four hundred fourteen million, one hundred fifty-two thousand, four hundred twenty-one".