20025505640 has 64 divisors (see below), whose sum is σ = 54523238400. Its totient is φ = 6462010368.

The previous prime is 20025505613. The next prime is 20025505649. The reversal of 20025505640 is 4650552002.

It is a super-2 number, since 2×20025505640² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20025505649) 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 15 ways as a sum of consecutive naturals, for example, 2098760 + ... + 2108279.

It is an arithmetic number, because the mean of its divisors is an integer number (851925600).

Almost surely, 2^20025505640 is an apocalyptic number.

20025505640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20025505640 is an abundant number, since it is smaller than the sum of its proper divisors (34497732760).

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

20025505640 is a wasteful number, since it uses less digits than its factorization.

20025505640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4207074 (or 4207070 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 29.

The spelling of 20025505640 in words is "twenty billion, twenty-five million, five hundred five thousand, six hundred forty".