20170471640 has 128 divisors (see below), whose sum is σ = 50379693120. Its totient is φ = 7206912000.

The previous prime is 20170471631. The next prime is 20170471669. The reversal of 20170471640 is 4617407102.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 20170471597 and 20170471606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6086624 + ... + 6089936.

Almost surely, 2^20170471640 is an apocalyptic number.

20170471640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20170471640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25189846560).

20170471640 is an abundant number, since it is smaller than the sum of its proper divisors (30209221480).

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

20170471640 is a wasteful number, since it uses less digits than its factorization.

20170471640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3573 (or 3569 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 32.

Adding to 20170471640 its reverse (4617407102), we get a palindrome (24787878742).

The spelling of 20170471640 in words is "twenty billion, one hundred seventy million, four hundred seventy-one thousand, six hundred forty".