1944821745 has 40 divisors (see below), whose sum is σ = 3491116200. Its totient is φ = 1035797760.

The previous prime is 1944821737. The next prime is 1944821771. The reversal of 1944821745 is 5471284491.

It can be written as a sum of positive squares in 4 ways, for example, as 28483569 + 1916338176 = 5337^2 + 43776^2 .

It is not a de Polignac number, because 1944821745 - 2³ = 1944821737 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1944821745.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 329581 + ... + 335429.

It is an arithmetic number, because the mean of its divisors is an integer number (87277905).

Almost surely, 2^1944821745 is an apocalyptic number.

1944821745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1944821745 is a deficient number, since it is larger than the sum of its proper divisors (1546294455).

1944821745 is an equidigital number, since it uses as much as digits as its factorization.

1944821745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6687 (or 6678 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 1944821745 is about 44100.1331630643. The cubic root of 1944821745 is about 1248.2261228119.

The spelling of 1944821745 in words is "one billion, nine hundred forty-four million, eight hundred twenty-one thousand, seven hundred forty-five".