4661721 has 24 divisors (see below), whose sum is σ = 7118280. Its totient is φ = 2935296.

The previous prime is 4661719. The next prime is 4661729. The reversal of 4661721 is 1271664.

4661721 is a `hidden beast` number, since 46 + 617 + 2 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 705600 + 3956121 = 840^2 + 1989^2 .

It is not a de Polignac number, because 4661721 - 2¹ = 4661719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4661729) 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 23 ways as a sum of consecutive naturals, for example, 13665 + ... + 14001.

It is an arithmetic number, because the mean of its divisors is an integer number (296595).

Almost surely, 2^4661721 is an apocalyptic number.

It is an amenable number.

4661721 is a deficient number, since it is larger than the sum of its proper divisors (2456559).

4661721 is a wasteful number, since it uses less digits than its factorization.

4661721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 425 (or 422 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 4661721 is about 2159.1018966228. The cubic root of 4661721 is about 167.0508767263.

It can be divided in two parts, 466 and 1721, that added together give a 7-th power (2187 = 3⁷).

The spelling of 4661721 in words is "four million, six hundred sixty-one thousand, seven hundred twenty-one".