1021978313 has 2 divisors, whose sum is σ = 1021978314. Its totient is φ = 1021978312.

The previous prime is 1021978301. The next prime is 1021978351. The reversal of 1021978313 is 3138791201.

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., 958026304 + 63952009 = 30952^2 + 7997^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021978313 - 2⁶ = 1021978249 is a prime.

It is not a weakly prime, because it can be changed into another prime (1021978393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510989156 + 510989157.

It is an arithmetic number, because the mean of its divisors is an integer number (510989157).

Almost surely, 2^1021978313 is an apocalyptic number.

It is an amenable number.

1021978313 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021978313 is an equidigital number, since it uses as much as digits as its factorization.

1021978313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 1021978313 is about 31968.3955337142. The cubic root of 1021978313 is about 1007.2730784207.

The spelling of 1021978313 in words is "one billion, twenty-one million, nine hundred seventy-eight thousand, three hundred thirteen".