863750021 has 2 divisors, whose sum is σ = 863750022. Its totient is φ = 863750020.

The previous prime is 863750011. The next prime is 863750033. The reversal of 863750021 is 120057368.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 704637025 + 159112996 = 26545^2 + 12614^2 .

It is a cyclic number.

It is not a de Polignac number, because 863750021 - 2¹⁰ = 863748997 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 863750021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (863750011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 431875010 + 431875011.

It is an arithmetic number, because the mean of its divisors is an integer number (431875011).

Almost surely, 2^863750021 is an apocalyptic number.

It is an amenable number.

863750021 is a deficient number, since it is larger than the sum of its proper divisors (1).

863750021 is an equidigital number, since it uses as much as digits as its factorization.

863750021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 863750021 is about 29389.6243766401. The cubic root of 863750021 is about 952.3487665504.

The spelling of 863750021 in words is "eight hundred sixty-three million, seven hundred fifty thousand, twenty-one".