21090098 has 8 divisors (see below), whose sum is σ = 33496092. Its totient is φ = 9924736.

The previous prime is 21090073. The next prime is 21090101. The reversal of 21090098 is 89009012.

It can be written as a sum of positive squares in 2 ways, for example, as 18003049 + 3087049 = 4243^2 + 1757^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 21090098.

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, 310115 + ... + 310182.

Almost surely, 2^21090098 is an apocalyptic number.

21090098 is a deficient number, since it is larger than the sum of its proper divisors (12405994).

21090098 is a wasteful number, since it uses less digits than its factorization.

21090098 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 620316.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 21090098 is about 4592.3956711067. The cubic root of 21090098 is about 276.2864158978.

The spelling of 21090098 in words is "twenty-one million, ninety thousand, ninety-eight".