20666179780 has 24 divisors (see below), whose sum is σ = 43604668800. Its totient is φ = 8227292640.

The previous prime is 20666179771. The next prime is 20666179789. The reversal of 20666179780 is 8797166602.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20666179771) and next prime (20666179789).

It is not an unprimeable number, because it can be changed into a prime (20666179789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2444380 + ... + 2452819.

It is an arithmetic number, because the mean of its divisors is an integer number (1816861200).

Almost surely, 2^20666179780 is an apocalyptic number.

20666179780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20666179780 is an abundant number, since it is smaller than the sum of its proper divisors (22938489020).

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

20666179780 is a wasteful number, since it uses less digits than its factorization.

20666179780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4897419 (or 4897417 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 52.

The spelling of 20666179780 in words is "twenty billion, six hundred sixty-six million, one hundred seventy-nine thousand, seven hundred eighty".