36667721 has 4 divisors (see below), whose sum is σ = 36689172. Its totient is φ = 36646272.

The previous prime is 36667717. The next prime is 36667751. The reversal of 36667721 is 12776663.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12776663 = 71 ⋅179953.

It can be written as a sum of positive squares in 2 ways, for example, as 17131321 + 19536400 = 4139^2 + 4420^2 .

It is a cyclic number.

It is not a de Polignac number, because 36667721 - 2² = 36667717 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (36667711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7916 + ... + 11661.

It is an arithmetic number, because the mean of its divisors is an integer number (9172293).

Almost surely, 2^36667721 is an apocalyptic number.

It is an amenable number.

36667721 is a deficient number, since it is larger than the sum of its proper divisors (21451).

36667721 is a wasteful number, since it uses less digits than its factorization.

36667721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21450.

The product of its digits is 63504, while the sum is 38.

The square root of 36667721 is about 6055.3877662789. The cubic root of 36667721 is about 332.2216820376.

The spelling of 36667721 in words is "thirty-six million, six hundred sixty-seven thousand, seven hundred twenty-one".