1664638400893 has 16 divisors (see below), whose sum is σ = 1864449723136. Its totient is φ = 1476250453440.

The previous prime is 1664638400891. The next prime is 1664638400897. The reversal of 1664638400893 is 3980048364661.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1664638400893 - 2¹ = 1664638400891 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664638400891) 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, 24374805 + ... + 24443002.

It is an arithmetic number, because the mean of its divisors is an integer number (116528107696).

Almost surely, 2^{1664638400893} is an apocalyptic number.

1664638400893 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1664638400893 is a deficient number, since it is larger than the sum of its proper divisors (199811322243).

1664638400893 is a wasteful number, since it uses less digits than its factorization.

1664638400893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48817924.

The product of its (nonzero) digits is 17915904, while the sum is 58.

The spelling of 1664638400893 in words is "one trillion, six hundred sixty-four billion, six hundred thirty-eight million, four hundred thousand, eight hundred ninety-three".