736664721 has 8 divisors (see below), whose sum is σ = 1057775040. Its totient is φ = 453332112.

The previous prime is 736664701. The next prime is 736664729. The reversal of 736664721 is 127466637.

It is a happy number.

736664721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 736664721 - 2¹¹ = 736662673 is a prime.

It is a super-2 number, since 2×736664721² = 1085349822332015682, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (736664729) 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, 9444381 + ... + 9444458.

It is an arithmetic number, because the mean of its divisors is an integer number (132221880).

Almost surely, 2^736664721 is an apocalyptic number.

It is an amenable number.

736664721 is a deficient number, since it is larger than the sum of its proper divisors (321110319).

736664721 is a wasteful number, since it uses less digits than its factorization.

736664721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18888855.

The product of its digits is 254016, while the sum is 42.

The square root of 736664721 is about 27141.5681381898. The cubic root of 736664721 is about 903.1432158313.

It can be divided in two parts, 73666 and 4721, that added together give a palindrome (78387).

The spelling of 736664721 in words is "seven hundred thirty-six million, six hundred sixty-four thousand, seven hundred twenty-one".