21403874 has 8 divisors (see below), whose sum is σ = 32492880. Its totient is φ = 10572916.

The previous prime is 21403849. The next prime is 21403883. The reversal of 21403874 is 47830412.

It is a sphenic number, since it is the product of 3 distinct primes.

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 in 3 ways as a sum of consecutive naturals, for example, 64304 + ... + 64635.

It is an arithmetic number, because the mean of its divisors is an integer number (4061610).

Almost surely, 2^21403874 is an apocalyptic number.

21403874 is a deficient number, since it is larger than the sum of its proper divisors (11089006).

21403874 is a wasteful number, since it uses less digits than its factorization.

21403874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129024.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 21403874 is about 4626.4321026035. The cubic root of 21403874 is about 277.6498619694.

The spelling of 21403874 in words is "twenty-one million, four hundred three thousand, eight hundred seventy-four".