83250721 has 2 divisors, whose sum is σ = 83250722. Its totient is φ = 83250720.

The previous prime is 83250719. The next prime is 83250737. The reversal of 83250721 is 12705238.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49900096 + 33350625 = 7064^2 + 5775^2 .

It is a cyclic number.

It is not a de Polignac number, because 83250721 - 2¹ = 83250719 is a prime.

Together with 83250719, it forms a pair of twin primes.

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 83250721.

It is not a weakly prime, because it can be changed into another prime (83250701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41625360 + 41625361.

It is an arithmetic number, because the mean of its divisors is an integer number (41625361).

Almost surely, 2^83250721 is an apocalyptic number.

It is an amenable number.

83250721 is a deficient number, since it is larger than the sum of its proper divisors (1).

83250721 is an equidigital number, since it uses as much as digits as its factorization.

83250721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 83250721 is about 9124.1833059184. The cubic root of 83250721 is about 436.6458476047.

Adding to 83250721 its reverse (12705238), we get a palindrome (95955959).

The spelling of 83250721 in words is "eighty-three million, two hundred fifty thousand, seven hundred twenty-one".