21674378 has 16 divisors (see below), whose sum is σ = 36427104. Its totient is φ = 9585360.

The previous prime is 21674377. The next prime is 21674381. The reversal of 21674378 is 87347612.

It is not an unprimeable number, because it can be changed into a prime (21674377) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12500 + ... + 14127.

It is an arithmetic number, because the mean of its divisors is an integer number (2276694).

Almost surely, 2^21674378 is an apocalyptic number.

21674378 is a deficient number, since it is larger than the sum of its proper divisors (14752726).

21674378 is a wasteful number, since it uses less digits than its factorization.

21674378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26677.

The product of its digits is 56448, while the sum is 38.

The square root of 21674378 is about 4655.5749376420. The cubic root of 21674378 is about 278.8146231558.

The spelling of 21674378 in words is "twenty-one million, six hundred seventy-four thousand, three hundred seventy-eight".