21090130 has 8 divisors (see below), whose sum is σ = 37962252. Its totient is φ = 8436048.

The previous prime is 21090127. The next prime is 21090143. The reversal of 21090130 is 3109012.

It can be written as a sum of positive squares in 2 ways, for example, as 20875761 + 214369 = 4569^2 + 463^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1054497 + ... + 1054516.

Almost surely, 2^21090130 is an apocalyptic number.

21090130 is a deficient number, since it is larger than the sum of its proper divisors (16872122).

21090130 is a wasteful number, since it uses less digits than its factorization.

21090130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2109020.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 21090130 is about 4592.3991551258. The cubic root of 21090130 is about 276.2865556342.

Adding to 21090130 its reverse (3109012), we get a palindrome (24199142).

The spelling of 21090130 in words is "twenty-one million, ninety thousand, one hundred thirty".