21066354 has 24 divisors (see below), whose sum is σ = 47218860. Its totient is φ = 6779808.

The previous prime is 21066347. The next prime is 21066359. The reversal of 21066354 is 45366012.

21066354 is a `hidden beast` number, since 21 + 0 + 6 + 635 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 19316025 + 1750329 = 4395^2 + 1323^2 .

It is not an unprimeable number, because it can be changed into a prime (21066359) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 19657 + ... + 20700.

Almost surely, 2^21066354 is an apocalyptic number.

21066354 is an abundant number, since it is smaller than the sum of its proper divisors (26152506).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21066354 is a wasteful number, since it uses less digits than its factorization.

21066354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40394 (or 40391 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 21066354 is about 4589.8097999808. The cubic root of 21066354 is about 276.1826925283.

It can be divided in two parts, 210 and 66354, that added together give a square (66564 = 258²).

The spelling of 21066354 in words is "twenty-one million, sixty-six thousand, three hundred fifty-four".