905621 has 2 divisors, whose sum is σ = 905622. Its totient is φ = 905620.

The previous prime is 905617. The next prime is 905629. The reversal of 905621 is 126509.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 835396 + 70225 = 914^2 + 265^2 .

It is a cyclic number.

It is not a de Polignac number, because 905621 - 2² = 905617 is a prime.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 905621.

It is not a weakly prime, because it can be changed into another prime (905629) 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, 452810 + 452811.

It is an arithmetic number, because the mean of its divisors is an integer number (452811).

2⁹⁰⁵⁶²¹ is an apocalyptic number.

It is an amenable number.

905621 is a deficient number, since it is larger than the sum of its proper divisors (1).

905621 is an equidigital number, since it uses as much as digits as its factorization.

905621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 905621 is about 951.6412139036. The cubic root of 905621 is about 96.7495220394.

The spelling of 905621 in words is "nine hundred five thousand, six hundred twenty-one".