204749621 has 2 divisors, whose sum is σ = 204749622. Its totient is φ = 204749620.

The previous prime is 204749609. The next prime is 204749663. The reversal of 204749621 is 126947402.

204749621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 141372100 + 63377521 = 11890^2 + 7961^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-204749621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204749221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102374810 + 102374811.

It is an arithmetic number, because the mean of its divisors is an integer number (102374811).

Almost surely, 2^204749621 is an apocalyptic number.

It is an amenable number.

204749621 is a deficient number, since it is larger than the sum of its proper divisors (1).

204749621 is an equidigital number, since it uses as much as digits as its factorization.

204749621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 204749621 is about 14309.0747779163. The cubic root of 204749621 is about 589.3967030524.

The spelling of 204749621 in words is "two hundred four million, seven hundred forty-nine thousand, six hundred twenty-one".