1644225652725 has 24 divisors (see below), whose sum is σ = 2746478380800. Its totient is φ = 867879928320.

The previous prime is 1644225652723. The next prime is 1644225652739. The reversal of 1644225652725 is 5272565224461.

It is not a de Polignac number, because 1644225652725 - 2¹ = 1644225652723 is a prime.

It is a super-3 number, since 3×1644225652725³ (a number of 38 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644225652721) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 112997925 + ... + 113012474.

It is an arithmetic number, because the mean of its divisors is an integer number (114436599200).

Almost surely, 2^{1644225652725} is an apocalyptic number.

1644225652725 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1644225652725 is a deficient number, since it is larger than the sum of its proper divisors (1102252728075).

1644225652725 is a wasteful number, since it uses less digits than its factorization.

1644225652725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226010509 (or 226010504 counting only the distinct ones).

The product of its digits is 8064000, while the sum is 51.

The spelling of 1644225652725 in words is "one trillion, six hundred forty-four billion, two hundred twenty-five million, six hundred fifty-two thousand, seven hundred twenty-five".