405022421 has 2 divisors, whose sum is σ = 405022422. Its totient is φ = 405022420.

The previous prime is 405022417. The next prime is 405022451. The reversal of 405022421 is 124220504.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 403447396 + 1575025 = 20086^2 + 1255^2 .

It is a cyclic number.

It is not a de Polignac number, because 405022421 - 2² = 405022417 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 405022393 and 405022402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405022451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202511210 + 202511211.

It is an arithmetic number, because the mean of its divisors is an integer number (202511211).

Almost surely, 2^405022421 is an apocalyptic number.

It is an amenable number.

405022421 is a deficient number, since it is larger than the sum of its proper divisors (1).

405022421 is an equidigital number, since it uses as much as digits as its factorization.

405022421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 405022421 is about 20125.1688440122. The cubic root of 405022421 is about 739.8772751190.

Adding to 405022421 its reverse (124220504), we get a palindrome (529242925).

The spelling of 405022421 in words is "four hundred five million, twenty-two thousand, four hundred twenty-one".