1644504540143 has 4 divisors (see below), whose sum is σ = 1697553073728. Its totient is φ = 1591456006560.

The previous prime is 1644504540121. The next prime is 1644504540181. The reversal of 1644504540143 is 3410454054461.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1644504540143 - 2⁶ = 1644504540079 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 1644504540143.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644504546143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26524266746 + ... + 26524266807.

It is an arithmetic number, because the mean of its divisors is an integer number (424388268432).

Almost surely, 2^{1644504540143} is an apocalyptic number.

1644504540143 is a deficient number, since it is larger than the sum of its proper divisors (53048533585).

1644504540143 is an equidigital number, since it uses as much as digits as its factorization.

1644504540143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53048533584.

The product of its (nonzero) digits is 460800, while the sum is 41.

The spelling of 1644504540143 in words is "one trillion, six hundred forty-four billion, five hundred four million, five hundred forty thousand, one hundred forty-three".