20517395472 has 320 divisors, whose sum is σ = 71563276800. Its totient is φ = 5513287680.

The previous prime is 20517395467. The next prime is 20517395473. The reversal of 20517395472 is 27459371502.

It is a happy number.

20517395472 is a `hidden beast` number, since 2 + 0 + 5 + 173 + 9 + 5 + 472 = 666.

It is a super-2 number, since 2×20517395472² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20517395473) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 14856222 + ... + 14857602.

It is an arithmetic number, because the mean of its divisors is an integer number (223635240).

Almost surely, 2^20517395472 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 20517395472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35781638400).

20517395472 is an abundant number, since it is smaller than the sum of its proper divisors (51045881328).

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

20517395472 is a wasteful number, since it uses less digits than its factorization.

20517395472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1456 (or 1410 counting only the distinct ones).

The product of its (nonzero) digits is 529200, while the sum is 45.

The spelling of 20517395472 in words is "twenty billion, five hundred seventeen million, three hundred ninety-five thousand, four hundred seventy-two".