21346740 has 60 divisors (see below), whose sum is σ = 66970596. Its totient is φ = 5692032.

The previous prime is 21346711. The next prime is 21346751. The reversal of 21346740 is 4764312.

It can be written as a sum of positive squares in 2 ways, for example, as 10732176 + 10614564 = 3276^2 + 3258^2 .

It is a tau number, because it is divible by the number of its divisors (60).

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 pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4969 + ... + 8208.

Almost surely, 2^21346740 is an apocalyptic number.

21346740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21346740 is an abundant number, since it is smaller than the sum of its proper divisors (45623856).

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

21346740 is a wasteful number, since it uses less digits than its factorization.

21346740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13198 (or 13187 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 21346740 is about 4620.2532398127. The cubic root of 21346740 is about 277.4025954710.

The spelling of 21346740 in words is "twenty-one million, three hundred forty-six thousand, seven hundred forty".