4688721 has 6 divisors (see below), whose sum is σ = 6772610. Its totient is φ = 3125808.

The previous prime is 4688707. The next prime is 4688741. The reversal of 4688721 is 1278864.

It can be written as a sum of positive squares in only one way, i.e., 3101121 + 1587600 = 1761^2 + 1260^2 .

It is not a de Polignac number, because 4688721 - 2¹⁸ = 4426577 is a prime.

It is a Duffinian number.

It is a Curzon number.

4688721 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (4688741) 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 5 ways as a sum of consecutive naturals, for example, 260476 + ... + 260493.

Almost surely, 2^4688721 is an apocalyptic number.

It is an amenable number.

4688721 is a deficient number, since it is larger than the sum of its proper divisors (2083889).

4688721 is a wasteful number, since it uses less digits than its factorization.

4688721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520975 (or 520972 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 4688721 is about 2165.3454689726. The cubic root of 4688721 is about 167.3727674169.

The spelling of 4688721 in words is "four million, six hundred eighty-eight thousand, seven hundred twenty-one".