752800021 has 2 divisors, whose sum is σ = 752800022. Its totient is φ = 752800020.

The previous prime is 752800019. The next prime is 752800033. The reversal of 752800021 is 120008257.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 596824900 + 155975121 = 24430^2 + 12489^2 .

It is a cyclic number.

It is not a de Polignac number, because 752800021 - 2¹ = 752800019 is a prime.

Together with 752800019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (752800421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 376400010 + 376400011.

It is an arithmetic number, because the mean of its divisors is an integer number (376400011).

Almost surely, 2^752800021 is an apocalyptic number.

It is an amenable number.

752800021 is a deficient number, since it is larger than the sum of its proper divisors (1).

752800021 is an equidigital number, since it uses as much as digits as its factorization.

752800021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 752800021 is about 27437.2014061201. The cubic root of 752800021 is about 909.6895535647.

Adding to 752800021 its reverse (120008257), we get a palindrome (872808278).

The spelling of 752800021 in words is "seven hundred fifty-two million, eight hundred thousand, twenty-one".