21553154 has 16 divisors (see below), whose sum is σ = 37008576. Its totient is φ = 9222000.

The previous prime is 21553141. The next prime is 21553157. The reversal of 21553154 is 45135512.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21553157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14129 + ... + 15579.

It is an arithmetic number, because the mean of its divisors is an integer number (2313036).

Almost surely, 2^21553154 is an apocalyptic number.

21553154 is a deficient number, since it is larger than the sum of its proper divisors (15455422).

21553154 is a wasteful number, since it uses less digits than its factorization.

21553154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2521.

The product of its digits is 3000, while the sum is 26.

The square root of 21553154 is about 4642.5374527299. The cubic root of 21553154 is about 278.2938510775.

Adding to 21553154 its reverse (45135512), we get a palindrome (66688666).

The spelling of 21553154 in words is "twenty-one million, five hundred fifty-three thousand, one hundred fifty-four".