21325763 has 4 divisors (see below), whose sum is σ = 21369000. Its totient is φ = 21282528.

The previous prime is 21325757. The next prime is 21325819. The reversal of 21325763 is 36752312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21325763 - 2¹⁰ = 21324739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21328763) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 20870 + ... + 21867.

It is an arithmetic number, because the mean of its divisors is an integer number (5342250).

Almost surely, 2^21325763 is an apocalyptic number.

21325763 is a deficient number, since it is larger than the sum of its proper divisors (43237).

21325763 is an equidigital number, since it uses as much as digits as its factorization.

21325763 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43236.

The product of its digits is 7560, while the sum is 29.

The square root of 21325763 is about 4617.9825681784. The cubic root of 21325763 is about 277.3116997592.

The spelling of 21325763 in words is "twenty-one million, three hundred twenty-five thousand, seven hundred sixty-three".