1315790921 has 2 divisors, whose sum is σ = 1315790922. Its totient is φ = 1315790920.

The previous prime is 1315790893. The next prime is 1315790941. The reversal of 1315790921 is 1290975131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1248632896 + 67158025 = 35336^2 + 8195^2 .

It is a cyclic number.

It is not a de Polignac number, because 1315790921 - 2³⁰ = 242049097 is a prime.

It is not a weakly prime, because it can be changed into another prime (1315790941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 657895460 + 657895461.

It is an arithmetic number, because the mean of its divisors is an integer number (657895461).

Almost surely, 2^1315790921 is an apocalyptic number.

It is an amenable number.

1315790921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1315790921 is an equidigital number, since it uses as much as digits as its factorization.

1315790921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17010, while the sum is 38.

The square root of 1315790921 is about 36273.8324553665. The cubic root of 1315790921 is about 1095.7941101984.

The spelling of 1315790921 in words is "one billion, three hundred fifteen million, seven hundred ninety thousand, nine hundred twenty-one".