21013355 has 8 divisors (see below), whose sum is σ = 27508464. Its totient is φ = 15282400.

The previous prime is 21013303. The next prime is 21013357. The reversal of 21013355 is 55331012.

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

It is not a de Polignac number, because 21013355 - 2¹⁰ = 21012331 is a prime.

It is a super-2 number, since 2×21013355² = 883122176712050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21013357) 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 7 ways as a sum of consecutive naturals, for example, 190976 + ... + 191085.

It is an arithmetic number, because the mean of its divisors is an integer number (3438558).

Almost surely, 2^21013355 is an apocalyptic number.

21013355 is a deficient number, since it is larger than the sum of its proper divisors (6495109).

21013355 is a wasteful number, since it uses less digits than its factorization.

21013355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382077.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 21013355 is about 4584.0326133220. The cubic root of 21013355 is about 275.9508900579.

Adding to 21013355 its reverse (55331012), we get a palindrome (76344367).

The spelling of 21013355 in words is "twenty-one million, thirteen thousand, three hundred fifty-five".