146666621 has 2 divisors, whose sum is σ = 146666622. Its totient is φ = 146666620.

The previous prime is 146666609. The next prime is 146666623. The reversal of 146666621 is 126666641.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 144264121 + 2402500 = 12011^2 + 1550^2 .

It is an emirp because it is prime and its reverse (126666641) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 146666621 - 2¹⁴ = 146650237 is a prime.

It is a super-2 number, since 2×146666621² = 43022195431115282, which contains 22 as substring.

Together with 146666623, 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 (146666623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 73333310 + 73333311.

It is an arithmetic number, because the mean of its divisors is an integer number (73333311).

Almost surely, 2^146666621 is an apocalyptic number.

It is an amenable number.

146666621 is a deficient number, since it is larger than the sum of its proper divisors (1).

146666621 is an equidigital number, since it uses as much as digits as its factorization.

146666621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62208, while the sum is 38.

The square root of 146666621 is about 12110.5995309894. The cubic root of 146666621 is about 527.3639381637.

The spelling of 146666621 in words is "one hundred forty-six million, six hundred sixty-six thousand, six hundred twenty-one".