21049898 has 4 divisors (see below), whose sum is σ = 31574850. Its totient is φ = 10524948.

The previous prime is 21049883. The next prime is 21049907. The reversal of 21049898 is 89894012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 13667809 + 7382089 = 3697^2 + 2717^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5262473 + ... + 5262476.

Almost surely, 2^21049898 is an apocalyptic number.

21049898 is a deficient number, since it is larger than the sum of its proper divisors (10524952).

21049898 is a wasteful number, since it uses less digits than its factorization.

21049898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10524951.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 21049898 is about 4588.0167828812. The cubic root of 21049898 is about 276.1107603482.

The spelling of 21049898 in words is "twenty-one million, forty-nine thousand, eight hundred ninety-eight".