21418000 has 40 divisors (see below), whose sum is σ = 51793560. Its totient is φ = 8566400.

The previous prime is 21417973. The next prime is 21418009. The reversal of 21418000 is 81412.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 147456 + 21270544 = 384^2 + 4612^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (21418009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3355 + ... + 7354.

It is an arithmetic number, because the mean of its divisors is an integer number (1294839).

Almost surely, 2^21418000 is an apocalyptic number.

21418000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21418000 is an abundant number, since it is smaller than the sum of its proper divisors (30375560).

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

21418000 is a wasteful number, since it uses less digits than its factorization.

21418000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10732 (or 10716 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 21418000 is about 4627.9585132108. The cubic root of 21418000 is about 277.7109290990.

Adding to 21418000 its reverse (81412), we get a palindrome (21499412).

The spelling of 21418000 in words is "twenty-one million, four hundred eighteen thousand".