21450337 has 2 divisors, whose sum is σ = 21450338. Its totient is φ = 21450336.

The previous prime is 21450323. The next prime is 21450347. The reversal of 21450337 is 73305412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20784481 + 665856 = 4559^2 + 816^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21450337 is a prime.

It is not a weakly prime, because it can be changed into another prime (21450347) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10725168 + 10725169.

It is an arithmetic number, because the mean of its divisors is an integer number (10725169).

Almost surely, 2^21450337 is an apocalyptic number.

It is an amenable number.

21450337 is a deficient number, since it is larger than the sum of its proper divisors (1).

21450337 is an equidigital number, since it uses as much as digits as its factorization.

21450337 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 25.

The square root of 21450337 is about 4631.4508525947. The cubic root of 21450337 is about 277.8506219209.

Adding to 21450337 its reverse (73305412), we get a palindrome (94755749).

The spelling of 21450337 in words is "twenty-one million, four hundred fifty thousand, three hundred thirty-seven".