20646404664466 has 24 divisors (see below), whose sum is σ = 36052223561856. Its totient is φ = 8841986181000.

The previous prime is 20646404664443. The next prime is 20646404664467. The reversal of 20646404664466 is 66446640464602.

It is a self number, because there is not a number n which added to its sum of digits gives 20646404664466.

It is not an unprimeable number, because it can be changed into a prime (20646404664467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 76924410 + ... + 77192341.

It is an arithmetic number, because the mean of its divisors is an integer number (1502175981744).

Almost surely, 2^{20646404664466} is an apocalyptic number.

20646404664466 is a deficient number, since it is larger than the sum of its proper divisors (15405818897390).

20646404664466 is a wasteful number, since it uses less digits than its factorization.

20646404664466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154118134 (or 154118127 counting only the distinct ones).

The product of its (nonzero) digits is 95551488, while the sum is 58.

The spelling of 20646404664466 in words is "twenty trillion, six hundred forty-six billion, four hundred four million, six hundred sixty-four thousand, four hundred sixty-six".