21667270 has 32 divisors (see below), whose sum is σ = 40914720. Its totient is φ = 8252160.

The previous prime is 21667253. The next prime is 21667271. The reversal of 21667270 is 7276612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21667271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17016 + ... + 18244.

It is an arithmetic number, because the mean of its divisors is an integer number (1278585).

Almost surely, 2^21667270 is an apocalyptic number.

21667270 is a deficient number, since it is larger than the sum of its proper divisors (19247450).

21667270 is a wasteful number, since it uses less digits than its factorization.

21667270 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1320.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 21667270 is about 4654.8114892013. The cubic root of 21667270 is about 278.7841412196.

The spelling of 21667270 in words is "twenty-one million, six hundred sixty-seven thousand, two hundred seventy".