1643245121001 has 32 divisors (see below), whose sum is σ = 2425025986560. Its totient is φ = 981408528000.

The previous prime is 1643245120997. The next prime is 1643245121071. The reversal of 1643245121001 is 1001215423461.

It is not a de Polignac number, because 1643245121001 - 2² = 1643245120997 is a prime.

It is a super-2 number, since 2×1643245121001² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1643245121001.

It is not an unprimeable number, because it can be changed into a prime (1643245121071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2476440 + ... + 3069078.

It is an arithmetic number, because the mean of its divisors is an integer number (75782062080).

Almost surely, 2^{1643245121001} is an apocalyptic number.

1643245121001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1643245121001 is a deficient number, since it is larger than the sum of its proper divisors (781780865559).

1643245121001 is a wasteful number, since it uses less digits than its factorization.

1643245121001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 593877.

The product of its (nonzero) digits is 5760, while the sum is 30.

The spelling of 1643245121001 in words is "one trillion, six hundred forty-three billion, two hundred forty-five million, one hundred twenty-one thousand, one".