21343761 has 12 divisors (see below), whose sum is σ = 30900480. Its totient is φ = 14196600.

The previous prime is 21343757. The next prime is 21343771. The reversal of 21343761 is 16734312.

It is not a de Polignac number, because 21343761 - 2² = 21343757 is a prime.

It is a super-2 number, since 2×21343761² = 911112267250242, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21343771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1836 + ... + 6786.

It is an arithmetic number, because the mean of its divisors is an integer number (2575040).

Almost surely, 2^21343761 is an apocalyptic number.

It is an amenable number.

21343761 is a deficient number, since it is larger than the sum of its proper divisors (9556719).

21343761 is a wasteful number, since it uses less digits than its factorization.

21343761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5436 (or 5433 counting only the distinct ones).

The product of its digits is 3024, while the sum is 27.

The square root of 21343761 is about 4619.9308436382. The cubic root of 21343761 is about 277.3896907562.

The spelling of 21343761 in words is "twenty-one million, three hundred forty-three thousand, seven hundred sixty-one".