21031107 has 8 divisors (see below), whose sum is σ = 28065984. Its totient is φ = 14008488.

The previous prime is 21031103. The next prime is 21031111. The reversal of 21031107 is 70113012.

It is an interprime number because it is at equal distance from previous prime (21031103) and next prime (21031111).

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

It is not a de Polignac number, because 21031107 - 2² = 21031103 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21031103) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2268 + ... + 6870.

It is an arithmetic number, because the mean of its divisors is an integer number (3508248).

Almost surely, 2^21031107 is an apocalyptic number.

21031107 is a deficient number, since it is larger than the sum of its proper divisors (7034877).

21031107 is a wasteful number, since it uses less digits than its factorization.

21031107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6129.

The product of its (nonzero) digits is 42, while the sum is 15.

The square root of 21031107 is about 4585.9684909515. The cubic root of 21031107 is about 276.0285755963.

Adding to 21031107 its reverse (70113012), we get a palindrome (91144119).

The spelling of 21031107 in words is "twenty-one million, thirty-one thousand, one hundred seven".