1643240006420 has 48 divisors (see below), whose sum is σ = 3455463659088. Its totient is φ = 656408862720.

The previous prime is 1643240006351. The next prime is 1643240006459. The reversal of 1643240006420 is 246000423461.

It can be written as a sum of positive squares in 8 ways, for example, as 241682358544 + 1401557647876 = 491612^2 + 1183874^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80065760 + ... + 80086280.

It is an arithmetic number, because the mean of its divisors is an integer number (71988826231).

Almost surely, 2^{1643240006420} is an apocalyptic number.

1643240006420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1643240006420 is an abundant number, since it is smaller than the sum of its proper divisors (1812223652668).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1643240006420 is a wasteful number, since it uses less digits than its factorization.

1643240006420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25740 (or 25738 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 32.

Adding to 1643240006420 its reverse (246000423461), we get a palindrome (1889240429881).

The spelling of 1643240006420 in words is "one trillion, six hundred forty-three billion, two hundred forty million, six thousand, four hundred twenty".