20520105640 has 32 divisors (see below), whose sum is σ = 48600252000. Its totient is φ = 7776039744.

The previous prime is 20520105587. The next prime is 20520105643. The reversal of 20520105640 is 4650102502.

It is not an unprimeable number, because it can be changed into a prime (20520105643) 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, 13499310 + ... + 13500829.

It is an arithmetic number, because the mean of its divisors is an integer number (1518757875).

Almost surely, 2^20520105640 is an apocalyptic number.

20520105640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20520105640 is an abundant number, since it is smaller than the sum of its proper divisors (28080146360).

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

20520105640 is a wasteful number, since it uses less digits than its factorization.

20520105640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27000169 (or 27000165 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The spelling of 20520105640 in words is "twenty billion, five hundred twenty million, one hundred five thousand, six hundred forty".