21264554 has 8 divisors (see below), whose sum is σ = 32498820. Its totient is φ = 10431616.

The previous prime is 21264541. The next prime is 21264559. The reversal of 21264554 is 45546212.

It can be written as a sum of positive squares in 2 ways, for example, as 20043529 + 1221025 = 4477^2 + 1105^2 .

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

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (21264559) 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 3 ways as a sum of consecutive naturals, for example, 100199 + ... + 100410.

Almost surely, 2^21264554 is an apocalyptic number.

21264554 is a deficient number, since it is larger than the sum of its proper divisors (11234266).

21264554 is a wasteful number, since it uses less digits than its factorization.

21264554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200664.

The product of its digits is 9600, while the sum is 29.

The square root of 21264554 is about 4611.3505613865. The cubic root of 21264554 is about 277.0461330628.

The spelling of 21264554 in words is "twenty-one million, two hundred sixty-four thousand, five hundred fifty-four".