21343760 has 20 divisors (see below), whose sum is σ = 49624428. Its totient is φ = 8537472.

The previous prime is 21343757. The next prime is 21343771. The reversal of 21343760 is 6734312.

It can be written as a sum of positive squares in 2 ways, for example, as 15272464 + 6071296 = 3908^2 + 2464^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133319 + ... + 133478.

Almost surely, 2^21343760 is an apocalyptic number.

21343760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21343760 is an abundant number, since it is smaller than the sum of its proper divisors (28280668).

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

21343760 is a wasteful number, since it uses less digits than its factorization.

21343760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266810 (or 266804 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 21343760 is about 4619.9307354115. The cubic root of 21343760 is about 277.3896864241.

The spelling of 21343760 in words is "twenty-one million, three hundred forty-three thousand, seven hundred sixty".