201662621 has 2 divisors, whose sum is σ = 201662622. Its totient is φ = 201662620.

The previous prime is 201662611. The next prime is 201662623. The reversal of 201662621 is 126266102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198105625 + 3556996 = 14075^2 + 1886^2 .

It is a cyclic number.

It is not a de Polignac number, because 201662621 - 2⁶ = 201662557 is a prime.

Together with 201662623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201662623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100831310 + 100831311.

It is an arithmetic number, because the mean of its divisors is an integer number (100831311).

Almost surely, 2^201662621 is an apocalyptic number.

It is an amenable number.

201662621 is a deficient number, since it is larger than the sum of its proper divisors (1).

201662621 is an equidigital number, since it uses as much as digits as its factorization.

201662621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 201662621 is about 14200.7964917465. The cubic root of 201662621 is about 586.4195888729.

The spelling of 201662621 in words is "two hundred one million, six hundred sixty-two thousand, six hundred twenty-one".