21417561266 has 8 divisors (see below), whose sum is σ = 32127031020. Its totient is φ = 10708550928.

The previous prime is 21417561239. The next prime is 21417561293. The reversal of 21417561266 is 66216571412.

It is an interprime number because it is at equal distance from previous prime (21417561239) and next prime (21417561293).

It can be written as a sum of positive squares in 2 ways, for example, as 14705200225 + 6712361041 = 121265^2 + 81929^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47720 + ... + 212396.

Almost surely, 2^21417561266 is an apocalyptic number.

21417561266 is a deficient number, since it is larger than the sum of its proper divisors (10709469754).

21417561266 is a wasteful number, since it uses less digits than its factorization.

21417561266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229708.

The product of its digits is 120960, while the sum is 41.

The spelling of 21417561266 in words is "twenty-one billion, four hundred seventeen million, five hundred sixty-one thousand, two hundred sixty-six".