21434880 has 80 divisors (see below), whose sum is σ = 68549184. Its totient is φ = 5713920.

The previous prime is 21434879. The next prime is 21434891. The reversal of 21434880 is 8843412.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×21434880² = 918908161228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6285 + ... + 9075.

Almost surely, 2^21434880 is an apocalyptic number.

21434880 is a gapful number since it is divisible by the number (20) 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 21434880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34274592).

21434880 is an abundant number, since it is smaller than the sum of its proper divisors (47114304).

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

21434880 is an equidigital number, since it uses as much as digits as its factorization.

21434880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2817 (or 2801 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 21434880 is about 4629.7818523123. The cubic root of 21434880 is about 277.7838666517.

The spelling of 21434880 in words is "twenty-one million, four hundred thirty-four thousand, eight hundred eighty".