66010021 has 8 divisors (see below), whose sum is σ = 82298304. Its totient is φ = 51436320.

The previous prime is 66010019. The next prime is 66010037. The reversal of 66010021 is 12001066.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66010021 - 2¹ = 66010019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66009977 and 66010004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66010421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 428560 + ... + 428713.

It is an arithmetic number, because the mean of its divisors is an integer number (10287288).

Almost surely, 2^66010021 is an apocalyptic number.

It is an amenable number.

66010021 is a deficient number, since it is larger than the sum of its proper divisors (16288283).

66010021 is a wasteful number, since it uses less digits than its factorization.

66010021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 857291.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 66010021 is about 8124.6551311425. The cubic root of 66010021 is about 404.1444541919.

Adding to 66010021 its reverse (12001066), we get a palindrome (78011087).

The spelling of 66010021 in words is "sixty-six million, ten thousand, twenty-one".