21171433679475 has 24 divisors (see below), whose sum is σ = 35051584888320. Its totient is φ = 11275899724320.

The previous prime is 21171433679449. The next prime is 21171433679479. The reversal of 21171433679475 is 57497633417112.

It is not a de Polignac number, because 21171433679475 - 2⁹ = 21171433678963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21171433679479) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 194089755 + ... + 194198804.

It is an arithmetic number, because the mean of its divisors is an integer number (1460482703680).

Almost surely, 2^{21171433679475} is an apocalyptic number.

21171433679475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21171433679475 is a deficient number, since it is larger than the sum of its proper divisors (13880151208845).

21171433679475 is a wasteful number, since it uses less digits than its factorization.

21171433679475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388289299 (or 388289294 counting only the distinct ones).

The product of its digits is 26671680, while the sum is 60.

The spelling of 21171433679475 in words is "twenty-one trillion, one hundred seventy-one billion, four hundred thirty-three million, six hundred seventy-nine thousand, four hundred seventy-five".