66830621 has 32 divisors (see below), whose sum is σ = 85494528. Its totient is φ = 51287040.

The previous prime is 66830611. The next prime is 66830627. The reversal of 66830621 is 12603866.

It is a cyclic number.

It is not a de Polignac number, because 66830621 - 2¹⁰ = 66829597 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 (66830627) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 89576 + ... + 90318.

It is an arithmetic number, because the mean of its divisors is an integer number (2671704).

Almost surely, 2^66830621 is an apocalyptic number.

It is an amenable number.

66830621 is a deficient number, since it is larger than the sum of its proper divisors (18663907).

66830621 is a wasteful number, since it uses less digits than its factorization.

66830621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 821.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 66830621 is about 8174.9997553517. Note that the first 3 decimals coincide. The cubic root of 66830621 is about 405.8122620414.

The spelling of 66830621 in words is "sixty-six million, eight hundred thirty thousand, six hundred twenty-one".