21357872266 has 64 divisors (see below), whose sum is σ = 35389509120. Its totient is φ = 9633944320.

The previous prime is 21357872231. The next prime is 21357872269. The reversal of 21357872266 is 66227875312.

It is not an unprimeable number, because it can be changed into a prime (21357872269) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20715171 + ... + 20716201.

It is an arithmetic number, because the mean of its divisors is an integer number (552961080).

Almost surely, 2^21357872266 is an apocalyptic number.

21357872266 is a deficient number, since it is larger than the sum of its proper divisors (14031636854).

21357872266 is a wasteful number, since it uses less digits than its factorization.

21357872266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1431.

The product of its digits is 1693440, while the sum is 49.

The spelling of 21357872266 in words is "twenty-one billion, three hundred fifty-seven million, eight hundred seventy-two thousand, two hundred sixty-six".