21418012 has 24 divisors (see below), whose sum is σ = 46730880. Its totient is φ = 8344560.

The previous prime is 21418009. The next prime is 21418013. The reversal of 21418012 is 21081412.

It is a happy number.

It is a super-3 number, since 3×21418012³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21418013) 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, 34462 + ... + 35077.

It is an arithmetic number, because the mean of its divisors is an integer number (1947120).

Almost surely, 2^21418012 is an apocalyptic number.

21418012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21418012 is an abundant number, since it is smaller than the sum of its proper divisors (25312868).

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

21418012 is a wasteful number, since it uses less digits than its factorization.

21418012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69561 (or 69559 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 21418012 is about 4627.9598096786. The cubic root of 21418012 is about 277.7109809639.

Adding to 21418012 its reverse (21081412), we get a palindrome (42499424).

It can be divided in two parts, 2141 and 8012, that added together give a triangular number (10153 = T₁₄₂).

The spelling of 21418012 in words is "twenty-one million, four hundred eighteen thousand, twelve".