916845821 has 2 divisors, whose sum is σ = 916845822. Its totient is φ = 916845820.

The previous prime is 916845767. The next prime is 916845833. The reversal of 916845821 is 128548619.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 800097796 + 116748025 = 28286^2 + 10805^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-916845821 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 (916845221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 458422910 + 458422911.

It is an arithmetic number, because the mean of its divisors is an integer number (458422911).

Almost surely, 2^916845821 is an apocalyptic number.

It is an amenable number.

916845821 is a deficient number, since it is larger than the sum of its proper divisors (1).

916845821 is an equidigital number, since it uses as much as digits as its factorization.

916845821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 44.

The square root of 916845821 is about 30279.4620328697. The cubic root of 916845821 is about 971.4760610774.

The spelling of 916845821 in words is "nine hundred sixteen million, eight hundred forty-five thousand, eight hundred twenty-one".