21146543415266 has 8 divisors (see below), whose sum is σ = 31750521626604. Its totient is φ = 10563036206400.

The previous prime is 21146543415209. The next prime is 21146543415269. The reversal of 21146543415266 is 66251434564112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21090459229225 + 56084186041 = 4592435^2 + 236821^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21146543415269) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5117748035 + ... + 5117752166.

Almost surely, 2^{21146543415266} is an apocalyptic number.

21146543415266 is a deficient number, since it is larger than the sum of its proper divisors (10603978211338).

21146543415266 is a wasteful number, since it uses less digits than its factorization.

21146543415266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10235501236.

The product of its digits is 4147200, while the sum is 50.

Adding to 21146543415266 its reverse (66251434564112), we get a palindrome (87397977979378).

The spelling of 21146543415266 in words is "twenty-one trillion, one hundred forty-six billion, five hundred forty-three million, four hundred fifteen thousand, two hundred sixty-six".