21266027 has 4 divisors (see below), whose sum is σ = 21419160. Its totient is φ = 21112896.

The previous prime is 21266017. The next prime is 21266029. The reversal of 21266027 is 72066212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21266027 - 2⁸ = 21265771 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21265987 and 21266005.

It is not an unprimeable number, because it can be changed into a prime (21266029) 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, 76358 + ... + 76635.

It is an arithmetic number, because the mean of its divisors is an integer number (5354790).

Almost surely, 2^21266027 is an apocalyptic number.

21266027 is a deficient number, since it is larger than the sum of its proper divisors (153133).

21266027 is a wasteful number, since it uses less digits than its factorization.

21266027 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153132.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 21266027 is about 4611.5102732185. The cubic root of 21266027 is about 277.0525299291.

The spelling of 21266027 in words is "twenty-one million, two hundred sixty-six thousand, twenty-seven".