21253814 has 4 divisors (see below), whose sum is σ = 31880724. Its totient is φ = 10626906.

The previous prime is 21253763. The next prime is 21253849. The reversal of 21253814 is 41835212.

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, 5313452 + ... + 5313455.

It is an arithmetic number, because the mean of its divisors is an integer number (7970181).

Almost surely, 2^21253814 is an apocalyptic number.

21253814 is a deficient number, since it is larger than the sum of its proper divisors (10626910).

21253814 is a wasteful number, since it uses less digits than its factorization.

21253814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10626909.

The product of its digits is 1920, while the sum is 26.

The square root of 21253814 is about 4610.1858964688. The cubic root of 21253814 is about 276.9994830281. Note that the first 3 decimals are identical.

The spelling of 21253814 in words is "twenty-one million, two hundred fifty-three thousand, eight hundred fourteen".