36639221 has 4 divisors (see below), whose sum is σ = 36757344. Its totient is φ = 36521100.

The previous prime is 36639217. The next prime is 36639227. The reversal of 36639221 is 12293663.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 36639221 - 2² = 36639217 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 (36639227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58595 + ... + 59216.

It is an arithmetic number, because the mean of its divisors is an integer number (9189336).

Almost surely, 2^36639221 is an apocalyptic number.

It is an amenable number.

36639221 is a deficient number, since it is larger than the sum of its proper divisors (118123).

36639221 is a wasteful number, since it uses less digits than its factorization.

36639221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118122.

The product of its digits is 11664, while the sum is 32.

The square root of 36639221 is about 6053.0340326154. The cubic root of 36639221 is about 332.1355865853.

The spelling of 36639221 in words is "thirty-six million, six hundred thirty-nine thousand, two hundred twenty-one".