1244651221 has 16 divisors (see below), whose sum is σ = 1430807040. Its totient is φ = 1070791920.

The previous prime is 1244651207. The next prime is 1244651237. The reversal of 1244651221 is 1221564421.

It is not a de Polignac number, because 1244651221 - 2⁵ = 1244651189 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1244651221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1244651201) 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, 232056 + ... + 237358.

It is an arithmetic number, because the mean of its divisors is an integer number (89425440).

Almost surely, 2^1244651221 is an apocalyptic number.

1244651221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1244651221 is a deficient number, since it is larger than the sum of its proper divisors (186155819).

1244651221 is a wasteful number, since it uses less digits than its factorization.

1244651221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6456.

The product of its digits is 3840, while the sum is 28.

The square root of 1244651221 is about 35279.6148079879. The cubic root of 1244651221 is about 1075.6786689107.

The spelling of 1244651221 in words is "one billion, two hundred forty-four million, six hundred fifty-one thousand, two hundred twenty-one".