21496913 has 2 divisors, whose sum is σ = 21496914. Its totient is φ = 21496912.

The previous prime is 21496903. The next prime is 21496939. The reversal of 21496913 is 31969412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14569489 + 6927424 = 3817^2 + 2632^2 .

It is a cyclic number.

It is not a de Polignac number, because 21496913 - 2¹² = 21492817 is a prime.

It is a super-3 number, since 3×21496913³ (a number of 23 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21496903) by changing a digit.

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 as a sum of consecutive naturals, namely, 10748456 + 10748457.

It is an arithmetic number, because the mean of its divisors is an integer number (10748457).

Almost surely, 2^21496913 is an apocalyptic number.

It is an amenable number.

21496913 is a deficient number, since it is larger than the sum of its proper divisors (1).

21496913 is an equidigital number, since it uses as much as digits as its factorization.

21496913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 35.

The square root of 21496913 is about 4636.4763560273. The cubic root of 21496913 is about 278.0515793742.

The spelling of 21496913 in words is "twenty-one million, four hundred ninety-six thousand, nine hundred thirteen".