21059107 has 4 divisors (see below), whose sum is σ = 22297896. Its totient is φ = 19820320.

The previous prime is 21059089. The next prime is 21059119. The reversal of 21059107 is 70195012.

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 21059107 - 2⁷ = 21058979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21059177) 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, 619369 + ... + 619402.

It is an arithmetic number, because the mean of its divisors is an integer number (5574474).

Almost surely, 2^21059107 is an apocalyptic number.

21059107 is a deficient number, since it is larger than the sum of its proper divisors (1238789).

21059107 is a wasteful number, since it uses less digits than its factorization.

21059107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1238788.

The product of its (nonzero) digits is 630, while the sum is 25.

The square root of 21059107 is about 4589.0202658084. The cubic root of 21059107 is about 276.1510191860.

The spelling of 21059107 in words is "twenty-one million, fifty-nine thousand, one hundred seven".