1645211556403 has 2 divisors, whose sum is σ = 1645211556404. Its totient is φ = 1645211556402.

The previous prime is 1645211556397. The next prime is 1645211556407. The reversal of 1645211556403 is 3046551125461.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1645211556403 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1645211556403.

It is not a weakly prime, because it can be changed into another prime (1645211556407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822605778201 + 822605778202.

It is an arithmetic number, because the mean of its divisors is an integer number (822605778202).

Almost surely, 2^{1645211556403} is an apocalyptic number.

1645211556403 is a deficient number, since it is larger than the sum of its proper divisors (1).

1645211556403 is an equidigital number, since it uses as much as digits as its factorization.

1645211556403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432000, while the sum is 43.

The spelling of 1645211556403 in words is "one trillion, six hundred forty-five billion, two hundred eleven million, five hundred fifty-six thousand, four hundred three".