21237075 has 36 divisors (see below), whose sum is σ = 39081328. Its totient is φ = 11016000.

The previous prime is 21237071. The next prime is 21237113. The reversal of 21237075 is 57073212.

It is not a de Polignac number, because 21237075 - 2² = 21237071 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21237071) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 7050 + ... + 9600.

Almost surely, 2^21237075 is an apocalyptic number.

21237075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21237075 is a deficient number, since it is larger than the sum of its proper divisors (17844253).

21237075 is a wasteful number, since it uses less digits than its factorization.

21237075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2604 (or 2596 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 27.

The square root of 21237075 is about 4608.3701023247. The cubic root of 21237075 is about 276.9267445205.

The spelling of 21237075 in words is "twenty-one million, two hundred thirty-seven thousand, seventy-five".