21130007 has 4 divisors (see below), whose sum is σ = 21151200. Its totient is φ = 21108816.

The previous prime is 21130001. The next prime is 21130027. The reversal of 21130007 is 70003112.

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 21130007 - 2⁶ = 21129943 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21129973 and 21130000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130001) 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, 9023 + ... + 11120.

It is an arithmetic number, because the mean of its divisors is an integer number (5287800).

Almost surely, 2^21130007 is an apocalyptic number.

21130007 is a deficient number, since it is larger than the sum of its proper divisors (21193).

21130007 is a wasteful number, since it uses less digits than its factorization.

21130007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21192.

The product of its (nonzero) digits is 42, while the sum is 14.

The square root of 21130007 is about 4596.7387352339. The cubic root of 21130007 is about 276.4605792549.

Adding to 21130007 its reverse (70003112), we get a palindrome (91133119).

The spelling of 21130007 in words is "twenty-one million, one hundred thirty thousand, seven".