643203621664435 has 48 divisors (see below), whose sum is σ = 893820014849664. Its totient is φ = 441491899140864.

The previous prime is 643203621664411. The next prime is 643203621664463. The reversal of 643203621664435 is 534466126302346.

It is not a de Polignac number, because 643203621664435 - 2²⁵ = 643203588110003 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 257352507 + ... + 259839796.

It is an arithmetic number, because the mean of its divisors is an integer number (18621250309368).

Almost surely, 2^{643203621664435} is an apocalyptic number.

643203621664435 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

643203621664435 is a deficient number, since it is larger than the sum of its proper divisors (250616393185229).

643203621664435 is a wasteful number, since it uses less digits than its factorization.

643203621664435 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517192412 (or 517192393 counting only the distinct ones).

The product of its (nonzero) digits is 44789760, while the sum is 55.

The spelling of 643203621664435 in words is "six hundred forty-three trillion, two hundred three billion, six hundred twenty-one million, six hundred sixty-four thousand, four hundred thirty-five".