21054554 has 8 divisors (see below), whose sum is σ = 32435508. Its totient is φ = 10242720.

The previous prime is 21054541. The next prime is 21054559. The reversal of 21054554 is 45545012.

It can be written as a sum of positive squares in 2 ways, for example, as 20948929 + 105625 = 4577^2 + 325^2 .

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

It is a super-3 number, since 3×21054554³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21054559) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 142187 + ... + 142334.

Almost surely, 2^21054554 is an apocalyptic number.

21054554 is a deficient number, since it is larger than the sum of its proper divisors (11380954).

21054554 is a wasteful number, since it uses less digits than its factorization.

21054554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284560.

The product of its (nonzero) digits is 4000, while the sum is 26.

The square root of 21054554 is about 4588.5241636064. The cubic root of 21054554 is about 276.1311163760.

Adding to 21054554 its reverse (45545012), we get a palindrome (66599566).

The spelling of 21054554 in words is "twenty-one million, fifty-four thousand, five hundred fifty-four".