21050398 has 4 divisors (see below), whose sum is σ = 31575600. Its totient is φ = 10525198.

The previous prime is 21050383. The next prime is 21050399. The reversal of 21050398 is 89305012.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21050399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5262598 + ... + 5262601.

It is an arithmetic number, because the mean of its divisors is an integer number (7893900).

Almost surely, 2^21050398 is an apocalyptic number.

21050398 is a deficient number, since it is larger than the sum of its proper divisors (10525202).

21050398 is a wasteful number, since it uses less digits than its factorization.

21050398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10525201.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 21050398 is about 4588.0712723322. The cubic root of 21050398 is about 276.1129464916.

The spelling of 21050398 in words is "twenty-one million, fifty thousand, three hundred ninety-eight".