20816171825 has 12 divisors (see below), whose sum is σ = 26009095728. Its totient is φ = 16525813200.

The previous prime is 20816171813. The next prime is 20816171923. The reversal of 20816171825 is 52817161802.

It is not a de Polignac number, because 20816171825 - 2⁴ = 20816171809 is a prime.

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3174767 + ... + 3181316.

It is an arithmetic number, because the mean of its divisors is an integer number (2167424644).

Almost surely, 2^20816171825 is an apocalyptic number.

20816171825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20816171825 is a deficient number, since it is larger than the sum of its proper divisors (5192923903).

20816171825 is a wasteful number, since it uses less digits than its factorization.

20816171825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6356224 (or 6356219 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 41.

The spelling of 20816171825 in words is "twenty billion, eight hundred sixteen million, one hundred seventy-one thousand, eight hundred twenty-five".