20433665664 has 128 divisors (see below), whose sum is σ = 60418108800. Its totient is φ = 6798753792.

The previous prime is 20433665591. The next prime is 20433665689. The reversal of 20433665664 is 46656633402.

20433665664 is a `hidden beast` number, since 20 + 4 + 3 + 3 + 66 + 566 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (128).

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, 1988989 + ... + 1999235.

It is an arithmetic number, because the mean of its divisors is an integer number (472016475).

Almost surely, 2^20433665664 is an apocalyptic number.

20433665664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20433665664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30209054400).

20433665664 is an abundant number, since it is smaller than the sum of its proper divisors (39984443136).

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

20433665664 is a wasteful number, since it uses less digits than its factorization.

20433665664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10847 (or 10829 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 45.

The spelling of 20433665664 in words is "twenty billion, four hundred thirty-three million, six hundred sixty-five thousand, six hundred sixty-four".