21137216266 has 8 divisors (see below), whose sum is σ = 32728593024. Its totient is φ = 10227685260.

The previous prime is 21137216161. The next prime is 21137216279. The reversal of 21137216266 is 66261273112.

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

It is a super-2 number, since 2×21137216266² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 170461360 + ... + 170461483.

It is an arithmetic number, because the mean of its divisors is an integer number (4091074128).

Almost surely, 2^21137216266 is an apocalyptic number.

21137216266 is a deficient number, since it is larger than the sum of its proper divisors (11591376758).

21137216266 is a wasteful number, since it uses less digits than its factorization.

21137216266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340922876.

The product of its digits is 36288, while the sum is 37.

Adding to 21137216266 its reverse (66261273112), we get a palindrome (87398489378).

The spelling of 21137216266 in words is "twenty-one billion, one hundred thirty-seven million, two hundred sixteen thousand, two hundred sixty-six".