21139011 has 6 divisors (see below), whose sum is σ = 30534140. Its totient is φ = 14092668.

The previous prime is 21139009. The next prime is 21139031. The reversal of 21139011 is 11093112.

It is not a de Polignac number, because 21139011 - 2¹ = 21139009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21139031) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1174381 + ... + 1174398.

Almost surely, 2^21139011 is an apocalyptic number.

21139011 is a deficient number, since it is larger than the sum of its proper divisors (9395129).

21139011 is a wasteful number, since it uses less digits than its factorization.

21139011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2348785 (or 2348782 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 18.

The square root of 21139011 is about 4597.7180209317. The cubic root of 21139011 is about 276.4998424942.

The spelling of 21139011 in words is "twenty-one million, one hundred thirty-nine thousand, eleven".