21070107 has 12 divisors (see below), whose sum is σ = 32036680. Its totient is φ = 13307328.

The previous prime is 21070103. The next prime is 21070117. The reversal of 21070107 is 70107012.

It is not a de Polignac number, because 21070107 - 2² = 21070103 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21070107.

It is not an unprimeable number, because it can be changed into a prime (21070103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61438 + ... + 61779.

Almost surely, 2^21070107 is an apocalyptic number.

21070107 is a deficient number, since it is larger than the sum of its proper divisors (10966573).

21070107 is a wasteful number, since it uses less digits than its factorization.

21070107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123242 (or 123239 counting only the distinct ones).

The product of its (nonzero) digits is 98, while the sum is 18.

The square root of 21070107 is about 4590.2186222445. The cubic root of 21070107 is about 276.1990923302.

Adding to 21070107 its reverse (70107012), we get a palindrome (91177119).

The spelling of 21070107 in words is "twenty-one million, seventy thousand, one hundred seven".