21348712 has 48 divisors (see below), whose sum is σ = 50807520. Its totient is φ = 8316000.

The previous prime is 21348661. The next prime is 21348713. The reversal of 21348712 is 21784312.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (21348713) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1837 + ... + 6787.

It is an arithmetic number, because the mean of its divisors is an integer number (1058490).

Almost surely, 2^21348712 is an apocalyptic number.

21348712 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21348712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25403760).

21348712 is an abundant number, since it is smaller than the sum of its proper divisors (29458808).

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

21348712 is a wasteful number, since it uses less digits than its factorization.

21348712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4982 (or 4971 counting only the distinct ones).

The product of its digits is 2688, while the sum is 28.

The square root of 21348712 is about 4620.4666431000. The cubic root of 21348712 is about 277.4111373073.

Subtracting 21348712 from its reverse (21784312), we obtain a square (435600 = 660²).

The spelling of 21348712 in words is "twenty-one million, three hundred forty-eight thousand, seven hundred twelve".