21363155 has 12 divisors (see below), whose sum is σ = 28178976. Its totient is φ = 15536400.

The previous prime is 21363149. The next prime is 21363161. The reversal of 21363155 is 55136312.

It is an interprime number because it is at equal distance from previous prime (21363149) and next prime (21363161).

It is not a de Polignac number, because 21363155 - 2⁸ = 21362899 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17051 + ... + 18260.

It is an arithmetic number, because the mean of its divisors is an integer number (2348248).

Almost surely, 2^21363155 is an apocalyptic number.

21363155 is a deficient number, since it is larger than the sum of its proper divisors (6815821).

21363155 is a wasteful number, since it uses less digits than its factorization.

21363155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35338 (or 35327 counting only the distinct ones).

The product of its digits is 2700, while the sum is 26.

The square root of 21363155 is about 4622.0293162203. The cubic root of 21363155 is about 277.4736819994.

Adding to 21363155 its reverse (55136312), we get a palindrome (76499467).

The spelling of 21363155 in words is "twenty-one million, three hundred sixty-three thousand, one hundred fifty-five".