66629421 has 6 divisors (see below), whose sum is σ = 96242510. Its totient is φ = 44419608.

The previous prime is 66629399. The next prime is 66629429. The reversal of 66629421 is 12492666.

It can be written as a sum of positive squares in only one way, i.e., 52272900 + 14356521 = 7230^2 + 3789^2 .

It is not a de Polignac number, because 66629421 - 2⁵ = 66629389 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66629429) 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 5 ways as a sum of consecutive naturals, for example, 3701626 + ... + 3701643.

Almost surely, 2^66629421 is an apocalyptic number.

It is an amenable number.

66629421 is a deficient number, since it is larger than the sum of its proper divisors (29613089).

66629421 is a wasteful number, since it uses less digits than its factorization.

66629421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7403275 (or 7403272 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 66629421 is about 8162.6846686614. The cubic root of 66629421 is about 405.4046070820.

The spelling of 66629421 in words is "sixty-six million, six hundred twenty-nine thousand, four hundred twenty-one".