20999999999895 has 64 divisors (see below), whose sum is σ = 38574132387840. Its totient is φ = 9556508880000.

The previous prime is 20999999999893. The next prime is 20999999999987. The reversal of 20999999999895 is 59899999999902.

It is not a de Polignac number, because 20999999999895 - 2¹ = 20999999999893 is a prime.

It is a super-2 number, since 2×20999999999895² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (105).

It is a junction number, because it is equal to n+sod(n) for n = 20999999999793 and 20999999999802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20999999999893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 48038416 + ... + 48473594.

It is an arithmetic number, because the mean of its divisors is an integer number (602720818560).

Almost surely, 2^{20999999999895} is an apocalyptic number.

20999999999895 is a deficient number, since it is larger than the sum of its proper divisors (17574132387945).

20999999999895 is a wasteful number, since it uses less digits than its factorization.

20999999999895 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437276.

The product of its (nonzero) digits is 278942752080, while the sum is 105.

The spelling of 20999999999895 in words is "twenty trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, eight hundred ninety-five".