63621 has 6 divisors (see below), whose sum is σ = 91910. Its totient is φ = 42408.

The previous prime is 63617. The next prime is 63629. The reversal of 63621 is 12636.

It is a happy number.

63621 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 50625 + 12996 = 225^2 + 114^2 .

It is not a de Polignac number, because 63621 - 2² = 63617 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 63594 and 63603.

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 63621.

It is not an unprimeable number, because it can be changed into a prime (63629) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3526 + ... + 3543.

2⁶³⁶²¹ is an apocalyptic number.

It is an amenable number.

63621 is a deficient number, since it is larger than the sum of its proper divisors (28289).

63621 is a wasteful number, since it uses less digits than its factorization.

63621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7075 (or 7072 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 63621 is about 252.2320360303. The cubic root of 63621 is about 39.9208852914.

The spelling of 63621 in words is "sixty-three thousand, six hundred twenty-one".