444213721 has 16 divisors (see below), whose sum is σ = 521015040. Its totient is φ = 370782720.

The previous prime is 444213719. The next prime is 444213727. The reversal of 444213721 is 127312444.

444213721 is a nontrivial binomial coefficient, being equal to C(29807, 2).

It is not a de Polignac number, because 444213721 - 2¹ = 444213719 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 444213721.

It is not an unprimeable number, because it can be changed into a prime (444213727) 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, 207585 + ... + 209713.

It is an arithmetic number, because the mean of its divisors is an integer number (32563440).

Almost surely, 2^444213721 is an apocalyptic number.

444213721 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

444213721 is the 29806-th triangular number.

444213721 is the 9936-th centered nonagonal number.

It is an amenable number.

444213721 is a deficient number, since it is larger than the sum of its proper divisors (76801319).

444213721 is a wasteful number, since it uses less digits than its factorization.

444213721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2904.

The product of its digits is 5376, while the sum is 28.

The square root of 444213721 is about 21076.3782704714. The cubic root of 444213721 is about 763.0107493045.

The spelling of 444213721 in words is "four hundred forty-four million, two hundred thirteen thousand, seven hundred twenty-one".