1644253144425 has 72 divisors (see below), whose sum is σ = 2952525401280. Its totient is φ = 874708502400.

The previous prime is 1644253144423. The next prime is 1644253144433. The reversal of 1644253144425 is 5244413524461.

1644253144425 is a `hidden beast` number, since 1 + 64 + 4 + 25 + 3 + 144 + 425 = 666.

It is not a de Polignac number, because 1644253144425 - 2¹ = 1644253144423 is a prime.

It is a super-3 number, since 3×1644253144425³ (a number of 38 digits) contains 333 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (1644253144423) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 217518796 + ... + 217526354.

It is an arithmetic number, because the mean of its divisors is an integer number (41007297240).

Almost surely, 2^{1644253144425} is an apocalyptic number.

1644253144425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1644253144425 is a deficient number, since it is larger than the sum of its proper divisors (1308272256855).

1644253144425 is a wasteful number, since it uses less digits than its factorization.

1644253144425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9903 (or 9895 counting only the distinct ones).

The product of its digits is 1843200, while the sum is 45.

Adding to 1644253144425 its reverse (5244413524461), we get a palindrome (6888666668886).

The spelling of 1644253144425 in words is "one trillion, six hundred forty-four billion, two hundred fifty-three million, one hundred forty-four thousand, four hundred twenty-five".