20564007620 has 24 divisors (see below), whose sum is σ = 46506294744. Its totient is φ = 7592864256.

The previous prime is 20564007571. The next prime is 20564007623. The reversal of 20564007620 is 2670046502.

It can be written as a sum of positive squares in 4 ways, for example, as 168169024 + 20395838596 = 12968^2 + 142814^2 .

It is not an unprimeable number, because it can be changed into a prime (20564007623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39545909 + ... + 39546428.

It is an arithmetic number, because the mean of its divisors is an integer number (1937762281).

Almost surely, 2^20564007620 is an apocalyptic number.

20564007620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20564007620 is an abundant number, since it is smaller than the sum of its proper divisors (25942287124).

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

20564007620 is a wasteful number, since it uses less digits than its factorization.

20564007620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79092359 (or 79092357 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 32.

The spelling of 20564007620 in words is "twenty billion, five hundred sixty-four million, seven thousand, six hundred twenty".