21975337 has 4 divisors (see below), whose sum is σ = 22390020. Its totient is φ = 21560656.

The previous prime is 21975323. The next prime is 21975347. The reversal of 21975337 is 73357912.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8696601 + 13278736 = 2949^2 + 3644^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21975337 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21975296 and 21975305.

It is not an unprimeable number, because it can be changed into a prime (21975307) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 207262 + ... + 207367.

It is an arithmetic number, because the mean of its divisors is an integer number (5597505).

Almost surely, 2^21975337 is an apocalyptic number.

It is an amenable number.

21975337 is a deficient number, since it is larger than the sum of its proper divisors (414683).

21975337 is an equidigital number, since it uses as much as digits as its factorization.

21975337 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414682.

The product of its digits is 39690, while the sum is 37.

The square root of 21975337 is about 4687.7859379455. The cubic root of 21975337 is about 280.0991867988.

The spelling of 21975337 in words is "twenty-one million, nine hundred seventy-five thousand, three hundred thirty-seven".