21324775 has 24 divisors (see below), whose sum is σ = 27498240. Its totient is φ = 16393440.

The previous prime is 21324769. The next prime is 21324781. The reversal of 21324775 is 57742312.

It is an interprime number because it is at equal distance from previous prime (21324769) and next prime (21324781).

It is not a de Polignac number, because 21324775 - 2⁹ = 21324263 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 89106 + ... + 89344.

It is an arithmetic number, because the mean of its divisors is an integer number (1145760).

Almost surely, 2^21324775 is an apocalyptic number.

21324775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21324775 is a deficient number, since it is larger than the sum of its proper divisors (6173465).

21324775 is a wasteful number, since it uses less digits than its factorization.

21324775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375 (or 370 counting only the distinct ones).

The product of its digits is 11760, while the sum is 31.

The square root of 21324775 is about 4617.8755938202. The cubic root of 21324775 is about 277.3074171740.

The spelling of 21324775 in words is "twenty-one million, three hundred twenty-four thousand, seven hundred seventy-five".