90621 has 6 divisors (see below), whose sum is σ = 130910. Its totient is φ = 60408.

The previous prime is 90619. The next prime is 90631. The reversal of 90621 is 12609.

It can be written as a sum of positive squares in only one way, i.e., 68121 + 22500 = 261^2 + 150^2 .

It is not a de Polignac number, because 90621 - 2¹ = 90619 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 90594 and 90603.

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 90621.

It is not an unprimeable number, because it can be changed into a prime (90631) 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 in 5 ways as a sum of consecutive naturals, for example, 5026 + ... + 5043.

2⁹⁰⁶²¹ is an apocalyptic number.

It is an amenable number.

90621 is a deficient number, since it is larger than the sum of its proper divisors (40289).

90621 is a wasteful number, since it uses less digits than its factorization.

90621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10075 (or 10072 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 90621 is about 301.0332207581. The cubic root of 90621 is about 44.9168836130.

The spelling of 90621 in words is "ninety thousand, six hundred twenty-one".