21386955 has 8 divisors (see below), whose sum is σ = 34219152. Its totient is φ = 11406368.

The previous prime is 21386947. The next prime is 21386971. The reversal of 21386955 is 55968312.

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

It is a cyclic number.

It is not a de Polignac number, because 21386955 - 2³ = 21386947 is a prime.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 712884 + ... + 712913.

It is an arithmetic number, because the mean of its divisors is an integer number (4277394).

Almost surely, 2^21386955 is an apocalyptic number.

21386955 is a deficient number, since it is larger than the sum of its proper divisors (12832197).

21386955 is a wasteful number, since it uses less digits than its factorization.

21386955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1425805.

The product of its digits is 64800, while the sum is 39.

The square root of 21386955 is about 4624.6032262238. The cubic root of 21386955 is about 277.5766852428.

The spelling of 21386955 in words is "twenty-one million, three hundred eighty-six thousand, nine hundred fifty-five".