43250021 has 2 divisors, whose sum is σ = 43250022. Its totient is φ = 43250020.

The previous prime is 43249993. The next prime is 43250029. The reversal of 43250021 is 12005234.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40322500 + 2927521 = 6350^2 + 1711^2 .

It is a cyclic number.

It is not a de Polignac number, because 43250021 - 2²² = 39055717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43250029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21625010 + 21625011.

It is an arithmetic number, because the mean of its divisors is an integer number (21625011).

Almost surely, 2^43250021 is an apocalyptic number.

It is an amenable number.

43250021 is a deficient number, since it is larger than the sum of its proper divisors (1).

43250021 is an equidigital number, since it uses as much as digits as its factorization.

43250021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 43250021 is about 6576.4748155832. The cubic root of 43250021 is about 351.0175043962.

Adding to 43250021 its reverse (12005234), we get a palindrome (55255255).

The spelling of 43250021 in words is "forty-three million, two hundred fifty thousand, twenty-one".