921790313 has 2 divisors, whose sum is σ = 921790314. Its totient is φ = 921790312.

The previous prime is 921790283. The next prime is 921790333. The reversal of 921790313 is 313097129.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 916393984 + 5396329 = 30272^2 + 2323^2 .

It is a cyclic number.

It is not a de Polignac number, because 921790313 - 2¹⁰ = 921789289 is a prime.

It is a super-2 number, since 2×921790313² = 1699394762281275938, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (921790333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460895156 + 460895157.

It is an arithmetic number, because the mean of its divisors is an integer number (460895157).

Almost surely, 2^921790313 is an apocalyptic number.

It is an amenable number.

921790313 is a deficient number, since it is larger than the sum of its proper divisors (1).

921790313 is an equidigital number, since it uses as much as digits as its factorization.

921790313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10206, while the sum is 35.

The square root of 921790313 is about 30360.9998682520. Note that the first 3 decimals coincide. The cubic root of 921790313 is about 973.2193009144.

The spelling of 921790313 in words is "nine hundred twenty-one million, seven hundred ninety thousand, three hundred thirteen".