21275270 has 16 divisors (see below), whose sum is σ = 39616560. Its totient is φ = 8216544.

The previous prime is 21275237. The next prime is 21275281. The reversal of 21275270 is 7257212.

It is a super-2 number, since 2×21275270² = 905274227145800, which contains 22 as substring.

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36392 + ... + 36971.

It is an arithmetic number, because the mean of its divisors is an integer number (2476035).

Almost surely, 2^21275270 is an apocalyptic number.

21275270 is a deficient number, since it is larger than the sum of its proper divisors (18341290).

21275270 is a wasteful number, since it uses less digits than its factorization.

21275270 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73399.

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 21275270 is about 4612.5123306068. The cubic root of 21275270 is about 277.0926631993.

The spelling of 21275270 in words is "twenty-one million, two hundred seventy-five thousand, two hundred seventy".