1643351455551 has 16 divisors (see below), whose sum is σ = 2384010787424. Its totient is φ = 1000867497984.

The previous prime is 1643351455547. The next prime is 1643351455583. The reversal of 1643351455551 is 1555541533461.

It is not a de Polignac number, because 1643351455551 - 2² = 1643351455547 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 1643351455551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643351455751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 217198366 + ... + 217205931.

It is an arithmetic number, because the mean of its divisors is an integer number (149000674214).

Almost surely, 2^{1643351455551} is an apocalyptic number.

1643351455551 is a deficient number, since it is larger than the sum of its proper divisors (740659331873).

1643351455551 is a wasteful number, since it uses less digits than its factorization.

1643351455551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434404410.

The product of its digits is 2700000, while the sum is 48.

It can be divided in two parts, 1643351 and 455551, that added together give a palindrome (2098902).

The spelling of 1643351455551 in words is "one trillion, six hundred forty-three billion, three hundred fifty-one million, four hundred fifty-five thousand, five hundred fifty-one".