21222415266 has 16 divisors (see below), whose sum is σ = 45709817664. Its totient is φ = 6529973904.

The previous prime is 21222415231. The next prime is 21222415303. The reversal of 21222415266 is 66251422212.

21222415266 = 13410² + 13411² + ... + 13526².

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136041046 + ... + 136041201.

It is an arithmetic number, because the mean of its divisors is an integer number (2856863604).

Almost surely, 2^21222415266 is an apocalyptic number.

21222415266 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21222415266 is an abundant number, since it is smaller than the sum of its proper divisors (24487402398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21222415266 is a wasteful number, since it uses less digits than its factorization.

21222415266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272082265.

The product of its digits is 23040, while the sum is 33.

Adding to 21222415266 its reverse (66251422212), we get a palindrome (87473837478).

The spelling of 21222415266 in words is "twenty-one billion, two hundred twenty-two million, four hundred fifteen thousand, two hundred sixty-six".