20851795464177 has 8 divisors (see below), whose sum is σ = 27829152757120. Its totient is φ = 13887817573680.

The previous prime is 20851795464169. The next prime is 20851795464233. The reversal of 20851795464177 is 77146459715802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20851795464177 - 2³ = 20851795464169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20851795464167) 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, 3344846974 + ... + 3344853207.

It is an arithmetic number, because the mean of its divisors is an integer number (3478644094640).

Almost surely, 2^{20851795464177} is an apocalyptic number.

It is an amenable number.

20851795464177 is a deficient number, since it is larger than the sum of its proper divisors (6977357292943).

20851795464177 is a wasteful number, since it uses less digits than its factorization.

20851795464177 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6689701223.

The product of its (nonzero) digits is 118540800, while the sum is 66.

The spelling of 20851795464177 in words is "twenty trillion, eight hundred fifty-one billion, seven hundred ninety-five million, four hundred sixty-four thousand, one hundred seventy-seven".