21471318 has 40 divisors (see below), whose sum is σ = 52489800. Its totient is φ = 6505920.

The previous prime is 21471301. The next prime is 21471337. The reversal of 21471318 is 81317412.

It is a super-2 number, since 2×21471318² = 922034993314248, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21471291 and 21471300.

It is a congruent number.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 4243 + ... + 7806.

It is an arithmetic number, because the mean of its divisors is an integer number (1312245).

Almost surely, 2^21471318 is an apocalyptic number.

21471318 is an abundant number, since it is smaller than the sum of its proper divisors (31018482).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21471318 is a wasteful number, since it uses less digits than its factorization.

21471318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12074 (or 12065 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 21471318 is about 4633.7153559536. The cubic root of 21471318 is about 277.9411828020.

The spelling of 21471318 in words is "twenty-one million, four hundred seventy-one thousand, three hundred eighteen".