21193513 has 8 divisors (see below), whose sum is σ = 23312736. Its totient is φ = 19265620.

The previous prime is 21193463. The next prime is 21193541. The reversal of 21193513 is 31539112.

It is not a de Polignac number, because 21193513 - 2¹⁷ = 21062441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21193583) 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 7 ways as a sum of consecutive naturals, for example, 6631 + ... + 9292.

It is an arithmetic number, because the mean of its divisors is an integer number (2914092).

Almost surely, 2^21193513 is an apocalyptic number.

It is an amenable number.

21193513 is a deficient number, since it is larger than the sum of its proper divisors (2119223).

21193513 is an equidigital number, since it uses as much as digits as its factorization.

21193513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15956 (or 15934 counting only the distinct ones).

The product of its digits is 810, while the sum is 25.

The square root of 21193513 is about 4603.6412762073. The cubic root of 21193513 is about 276.7372686384.

The spelling of 21193513 in words is "twenty-one million, one hundred ninety-three thousand, five hundred thirteen".