918357821 has 2 divisors, whose sum is σ = 918357822. Its totient is φ = 918357820.

The previous prime is 918357793. The next prime is 918357827. The reversal of 918357821 is 128753819.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 544708921 + 373648900 = 23339^2 + 19330^2 .

It is a cyclic number.

It is not a de Polignac number, because 918357821 - 2⁶ = 918357757 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (918357827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 459178910 + 459178911.

It is an arithmetic number, because the mean of its divisors is an integer number (459178911).

Almost surely, 2^918357821 is an apocalyptic number.

It is an amenable number.

918357821 is a deficient number, since it is larger than the sum of its proper divisors (1).

918357821 is an equidigital number, since it uses as much as digits as its factorization.

918357821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 44.

The square root of 918357821 is about 30304.4191661876. The cubic root of 918357821 is about 972.0097986136.

The spelling of 918357821 in words is "nine hundred eighteen million, three hundred fifty-seven thousand, eight hundred twenty-one".