66402621 has 12 divisors (see below), whose sum is σ = 98146048. Its totient is φ = 43238664.

The previous prime is 66402607. The next prime is 66402643. The reversal of 66402621 is 12620466.

It is a happy number.

It is not a de Polignac number, because 66402621 - 2¹³ = 66394429 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 (66402521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 85405 + ... + 86178.

Almost surely, 2^66402621 is an apocalyptic number.

It is an amenable number.

66402621 is a deficient number, since it is larger than the sum of its proper divisors (31743427).

66402621 is a wasteful number, since it uses less digits than its factorization.

66402621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171632 (or 171629 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 66402621 is about 8148.7803381856. The cubic root of 66402621 is about 404.9440983657.

It can be divided in two parts, 6640 and 2621, that added together give a cube (9261 = 21³).

The spelling of 66402621 in words is "sixty-six million, four hundred two thousand, six hundred twenty-one".