21340100 has 36 divisors (see below), whose sum is σ = 49035924. Its totient is φ = 8033280.

The previous prime is 21340093. The next prime is 21340141. The reversal of 21340100 is 104312.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 2815684 + 18524416 = 1678^2 + 4304^2 .

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 11 ways as a sum of consecutive naturals, for example, 4577 + ... + 7976.

It is an arithmetic number, because the mean of its divisors is an integer number (1362109).

Almost surely, 2^21340100 is an apocalyptic number.

21340100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21340100 is an abundant number, since it is smaller than the sum of its proper divisors (27695824).

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

21340100 is a wasteful number, since it uses less digits than its factorization.

21340100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12584 (or 12577 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 21340100 is about 4619.5346085942. The cubic root of 21340100 is about 277.3738300444.

Adding to 21340100 its reverse (104312), we get a palindrome (21444412).

The spelling of 21340100 in words is "twenty-one million, three hundred forty thousand, one hundred".