21274145 has 8 divisors (see below), whose sum is σ = 25837056. Its totient is φ = 16813936.

The previous prime is 21274133. The next prime is 21274159. The reversal of 21274145 is 54147212.

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

It is a cyclic number.

It is not a de Polignac number, because 21274145 - 2¹⁰ = 21273121 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian 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, 25217 + ... + 26046.

It is an arithmetic number, because the mean of its divisors is an integer number (3229632).

Almost surely, 2^21274145 is an apocalyptic number.

It is an amenable number.

21274145 is a deficient number, since it is larger than the sum of its proper divisors (4562911).

21274145 is an equidigital number, since it uses as much as digits as its factorization.

21274145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51351.

The product of its digits is 2240, while the sum is 26.

The square root of 21274145 is about 4612.3903781011. The cubic root of 21274145 is about 277.0877790507.

The spelling of 21274145 in words is "twenty-one million, two hundred seventy-four thousand, one hundred forty-five".