21145130 has 16 divisors (see below), whose sum is σ = 39090600. Its totient is φ = 8229312.

The previous prime is 21145109. The next prime is 21145141. The reversal of 21145130 is 3154112.

It can be written as a sum of positive squares in 4 ways, for example, as 15389929 + 5755201 = 3923^2 + 2399^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21145099 and 21145108.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28205 + ... + 28944.

Almost surely, 2^21145130 is an apocalyptic number.

21145130 is a deficient number, since it is larger than the sum of its proper divisors (17945470).

21145130 is a wasteful number, since it uses less digits than its factorization.

21145130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57193.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 21145130 is about 4598.3834115915. The cubic root of 21145130 is about 276.5265189127.

Adding to 21145130 its reverse (3154112), we get a palindrome (24299242).

The spelling of 21145130 in words is "twenty-one million, one hundred forty-five thousand, one hundred thirty".