36009721 has 6 divisors (see below), whose sum is σ = 39581066. Its totient is φ = 32736000.

The previous prime is 36009713. The next prime is 36009739. The reversal of 36009721 is 12790063.

It can be written as a sum of positive squares in only one way, i.e., 35940025 + 69696 = 5995^2 + 264^2 .

It is not a de Polignac number, because 36009721 - 2³ = 36009713 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 36009721.

It is not an unprimeable number, because it can be changed into a prime (36009751) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 148680 + ... + 148921.

Almost surely, 2^36009721 is an apocalyptic number.

It is an amenable number.

36009721 is a deficient number, since it is larger than the sum of its proper divisors (3571345).

36009721 is a wasteful number, since it uses less digits than its factorization.

36009721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297623 (or 297612 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 28.

The square root of 36009721 is about 6000.8100286545. The cubic root of 36009721 is about 330.2224426173. Note that the first 3 decimals are identical.

Adding to 36009721 its reverse (12790063), we get a palindrome (48799784).

The spelling of 36009721 in words is "thirty-six million, nine thousand, seven hundred twenty-one".