4087721 has 16 divisors (see below), whose sum is σ = 4727808. Its totient is φ = 3498000.

The previous prime is 4087711. The next prime is 4087729. The reversal of 4087721 is 1277804.

4087721 = 140² + 141² + ... + 246².

It is not a de Polignac number, because 4087721 - 2¹⁴ = 4071337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4087729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26996 + ... + 27146.

It is an arithmetic number, because the mean of its divisors is an integer number (295488).

Almost surely, 2^4087721 is an apocalyptic number.

It is an amenable number.

4087721 is a deficient number, since it is larger than the sum of its proper divisors (640087).

4087721 is a wasteful number, since it uses less digits than its factorization.

4087721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292.

The product of its (nonzero) digits is 3136, while the sum is 29.

The square root of 4087721 is about 2021.8113166169. The cubic root of 4087721 is about 159.8921278096.

The spelling of 4087721 in words is "four million, eighty-seven thousand, seven hundred twenty-one".