36555721 has 4 divisors (see below), whose sum is σ = 36719872. Its totient is φ = 36391572.

The previous prime is 36555709. The next prime is 36555731. The reversal of 36555721 is 12755563.

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 36555721 - 2¹⁷ = 36424649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (36555731) 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, 81741 + ... + 82186.

It is an arithmetic number, because the mean of its divisors is an integer number (9179968).

Almost surely, 2^36555721 is an apocalyptic number.

It is an amenable number.

36555721 is a deficient number, since it is larger than the sum of its proper divisors (164151).

36555721 is a wasteful number, since it uses less digits than its factorization.

36555721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164150.

The product of its digits is 31500, while the sum is 34.

The square root of 36555721 is about 6046.1327309281. The cubic root of 36555721 is about 331.8830847096.

The spelling of 36555721 in words is "thirty-six million, five hundred fifty-five thousand, seven hundred twenty-one".