20817314877646 has 32 divisors (see below), whose sum is σ = 35958416965632. Its totient is φ = 8853948660960.

The previous prime is 20817314877641. The next prime is 20817314877703. The reversal of 20817314877646 is 64677841371802.

It is a super-2 number, since 2×20817314877646² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (64) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20817314877641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4056526 + ... + 7621681.

It is an arithmetic number, because the mean of its divisors is an integer number (1123700530176).

Almost surely, 2^{20817314877646} is an apocalyptic number.

20817314877646 is a deficient number, since it is larger than the sum of its proper divisors (15141102087986).

20817314877646 is a wasteful number, since it uses less digits than its factorization.

20817314877646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11679184.

The product of its (nonzero) digits is 75866112, while the sum is 64.

The spelling of 20817314877646 in words is "twenty trillion, eight hundred seventeen billion, three hundred fourteen million, eight hundred seventy-seven thousand, six hundred forty-six".