355206421 has 2 divisors, whose sum is σ = 355206422. Its totient is φ = 355206420.

The previous prime is 355206409. The next prime is 355206431. The reversal of 355206421 is 124602553.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 320231025 + 34975396 = 17895^2 + 5914^2 .

It is an emirp because it is prime and its reverse (124602553) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 355206421 - 2⁵ = 355206389 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 355206421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (355206431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 177603210 + 177603211.

It is an arithmetic number, because the mean of its divisors is an integer number (177603211).

Almost surely, 2^355206421 is an apocalyptic number.

It is an amenable number.

355206421 is a deficient number, since it is larger than the sum of its proper divisors (1).

355206421 is an equidigital number, since it uses as much as digits as its factorization.

355206421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 355206421 is about 18846.9207299230. The cubic root of 355206421 is about 708.2070884152.

Adding to 355206421 its reverse (124602553), we get a palindrome (479808974).

The spelling of 355206421 in words is "three hundred fifty-five million, two hundred six thousand, four hundred twenty-one".