3872316721 has 16 divisors (see below), whose sum is σ = 4768887424. Its totient is φ = 3061908864.

The previous prime is 3872316719. The next prime is 3872316739. The reversal of 3872316721 is 1276132783.

It is a happy number.

It is not a de Polignac number, because 3872316721 - 2¹ = 3872316719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3872316751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144445 + ... + 169141.

It is an arithmetic number, because the mean of its divisors is an integer number (298055464).

Almost surely, 2^3872316721 is an apocalyptic number.

It is an amenable number.

3872316721 is a deficient number, since it is larger than the sum of its proper divisors (896570703).

3872316721 is a wasteful number, since it uses less digits than its factorization.

3872316721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26440.

The product of its digits is 84672, while the sum is 40.

The square root of 3872316721 is about 62227.9416419987. The cubic root of 3872316721 is about 1570.3276962125.

The spelling of 3872316721 in words is "three billion, eight hundred seventy-two million, three hundred sixteen thousand, seven hundred twenty-one".