21321468 has 180 divisors, whose sum is σ = 69521760. Its totient is φ = 5660928.

The previous prime is 21321449. The next prime is 21321481. The reversal of 21321468 is 86412312.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 269853 + ... + 269931.

It is an arithmetic number, because the mean of its divisors is an integer number (386232).

Almost surely, 2^21321468 is an apocalyptic number.

21321468 is a gapful number since it is divisible by the number (28) 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 21321468, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34760880).

21321468 is an abundant number, since it is smaller than the sum of its proper divisors (48200292).

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

21321468 is a wasteful number, since it uses less digits than its factorization.

21321468 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126 (or 108 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 21321468 is about 4617.5175148558. The cubic root of 21321468 is about 277.2930816880.

It can be divided in two parts, 2132 and 1468, that added together give a square (3600 = 60²).

The spelling of 21321468 in words is "twenty-one million, three hundred twenty-one thousand, four hundred sixty-eight".