21011707 has 8 divisors (see below), whose sum is σ = 21790080. Its totient is φ = 20239680.

The previous prime is 21011693. The next prime is 21011713. The reversal of 21011707 is 70711012.

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

It is a cyclic number.

It is not a de Polignac number, because 21011707 - 2⁷ = 21011579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21011807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5769 + ... + 8677.

It is an arithmetic number, because the mean of its divisors is an integer number (2723760).

Almost surely, 2^21011707 is an apocalyptic number.

21011707 is a deficient number, since it is larger than the sum of its proper divisors (778373).

21011707 is a wasteful number, since it uses less digits than its factorization.

21011707 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3173.

The product of its (nonzero) digits is 98, while the sum is 19.

The square root of 21011707 is about 4583.8528554045. The cubic root of 21011707 is about 275.9436759322.

Adding to 21011707 its reverse (70711012), we get a palindrome (91722719).

The spelling of 21011707 in words is "twenty-one million, eleven thousand, seven hundred seven".