21359155 has 16 divisors (see below), whose sum is σ = 27111168. Its totient is φ = 16128000.

The previous prime is 21359153. The next prime is 21359183. The reversal of 21359155 is 55195312.

It is not a de Polignac number, because 21359155 - 2¹ = 21359153 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (21359153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4675 + ... + 8035.

It is an arithmetic number, because the mean of its divisors is an integer number (1694448).

Almost surely, 2^21359155 is an apocalyptic number.

21359155 is a deficient number, since it is larger than the sum of its proper divisors (5752013).

21359155 is a wasteful number, since it uses less digits than its factorization.

21359155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3438.

The product of its digits is 6750, while the sum is 31.

The square root of 21359155 is about 4621.5965855968. The cubic root of 21359155 is about 277.4563630218.

The spelling of 21359155 in words is "twenty-one million, three hundred fifty-nine thousand, one hundred fifty-five".