20380628640 has 48 divisors (see below), whose sum is σ = 64198981728. Its totient is φ = 5434834176.

The previous prime is 20380628617. The next prime is 20380628641. The reversal of 20380628640 is 4682608302.

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (20380628641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21229342 + ... + 21230301.

It is an arithmetic number, because the mean of its divisors is an integer number (1337478786).

Almost surely, 2^20380628640 is an apocalyptic number.

20380628640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20380628640 is an abundant number, since it is smaller than the sum of its proper divisors (43818353088).

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

20380628640 is a wasteful number, since it uses less digits than its factorization.

20380628640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42459661 (or 42459653 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 39.

The spelling of 20380628640 in words is "twenty billion, three hundred eighty million, six hundred twenty-eight thousand, six hundred forty".