63666213 has 8 divisors (see below), whose sum is σ = 91418208. Its totient is φ = 39179184.

The previous prime is 63666203. The next prime is 63666217. The reversal of 63666213 is 31266636.

It is a happy number.

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

It is not a de Polignac number, because 63666213 - 2⁶ = 63666149 is a prime.

It is a super-2 number, since 2×63666213² = 8106773355522738, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63666217) 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, 816195 + ... + 816272.

It is an arithmetic number, because the mean of its divisors is an integer number (11427276).

Almost surely, 2^63666213 is an apocalyptic number.

It is an amenable number.

63666213 is a deficient number, since it is larger than the sum of its proper divisors (27751995).

63666213 is a wasteful number, since it uses less digits than its factorization.

63666213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1632483.

The product of its digits is 23328, while the sum is 33.

The square root of 63666213 is about 7979.1110407112. Note that the first 3 decimals coincide. The cubic root of 63666213 is about 399.3033979850.

The spelling of 63666213 in words is "sixty-three million, six hundred sixty-six thousand, two hundred thirteen".