146668021 has 4 divisors (see below), whose sum is σ = 147276844. Its totient is φ = 146059200.

The previous prime is 146668009. The next prime is 146668043. The reversal of 146668021 is 120866641.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120866641 = 7 ⋅17266663.

It can be written as a sum of positive squares in 2 ways, for example, as 85359121 + 61308900 = 9239^2 + 7830^2 .

It is a cyclic number.

It is not a de Polignac number, because 146668021 - 2¹¹ = 146665973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (146660021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 304050 + ... + 304531.

It is an arithmetic number, because the mean of its divisors is an integer number (36819211).

Almost surely, 2^146668021 is an apocalyptic number.

It is an amenable number.

146668021 is a deficient number, since it is larger than the sum of its proper divisors (608823).

146668021 is an equidigital number, since it uses as much as digits as its factorization.

146668021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608822.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 146668021 is about 12110.6573314581. The cubic root of 146668021 is about 527.3656161350.

The spelling of 146668021 in words is "one hundred forty-six million, six hundred sixty-eight thousand, twenty-one".