20475318556 has 144 divisors (see below), whose sum is σ = 46950285312. Its totient is φ = 7720272000.

The previous prime is 20475318553. The next prime is 20475318559. The reversal of 20475318556 is 65581357402.

It is an interprime number because it is at equal distance from previous prime (20475318553) and next prime (20475318559).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20475318553) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17788581 + ... + 17789731.

It is an arithmetic number, because the mean of its divisors is an integer number (326043648).

Almost surely, 2^20475318556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20475318556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23475142656).

20475318556 is an abundant number, since it is smaller than the sum of its proper divisors (26474966756).

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

20475318556 is a wasteful number, since it uses less digits than its factorization.

20475318556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1440 (or 1431 counting only the distinct ones).

The product of its (nonzero) digits is 1008000, while the sum is 46.

The spelling of 20475318556 in words is "twenty billion, four hundred seventy-five million, three hundred eighteen thousand, five hundred fifty-six".