1530456721 has 2 divisors, whose sum is σ = 1530456722. Its totient is φ = 1530456720.

The previous prime is 1530456703. The next prime is 1530456743. The reversal of 1530456721 is 1276540351.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1459240000 + 71216721 = 38200^2 + 8439^2 .

It is a cyclic number.

It is not a de Polignac number, because 1530456721 - 2⁵ = 1530456689 is a prime.

It is not a weakly prime, because it can be changed into another prime (1530456751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 765228360 + 765228361.

It is an arithmetic number, because the mean of its divisors is an integer number (765228361).

Almost surely, 2^1530456721 is an apocalyptic number.

It is an amenable number.

1530456721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1530456721 is an equidigital number, since it uses as much as digits as its factorization.

1530456721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25200, while the sum is 34.

The square root of 1530456721 is about 39121.0521458715. The cubic root of 1530456721 is about 1152.4099985085.

The spelling of 1530456721 in words is "one billion, five hundred thirty million, four hundred fifty-six thousand, seven hundred twenty-one".