21210914 has 4 divisors (see below), whose sum is σ = 31816374. Its totient is φ = 10605456.

The previous prime is 21210907. The next prime is 21210929. The reversal of 21210914 is 41901212.

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., 21003889 + 207025 = 4583^2 + 455^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5302727 + ... + 5302730.

Almost surely, 2^21210914 is an apocalyptic number.

21210914 is a deficient number, since it is larger than the sum of its proper divisors (10605460).

21210914 is a wasteful number, since it uses less digits than its factorization.

21210914 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10605459.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 21210914 is about 4605.5308054555. The cubic root of 21210914 is about 276.8129865854.

The spelling of 21210914 in words is "twenty-one million, two hundred ten thousand, nine hundred fourteen".