21075814 has 4 divisors (see below), whose sum is σ = 31613724. Its totient is φ = 10537906.

The previous prime is 21075809. The next prime is 21075827. The reversal of 21075814 is 41857012.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5268952 + ... + 5268955.

It is an arithmetic number, because the mean of its divisors is an integer number (7903431).

Almost surely, 2^21075814 is an apocalyptic number.

21075814 is a deficient number, since it is larger than the sum of its proper divisors (10537910).

21075814 is a wasteful number, since it uses less digits than its factorization.

21075814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10537909.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 21075814 is about 4590.8402281064. The cubic root of 21075814 is about 276.2240269596.

It can be divided in two parts, 2107 and 5814, that added together give a square (7921 = 89²).

The spelling of 21075814 in words is "twenty-one million, seventy-five thousand, eight hundred fourteen".