720645427 has 2 divisors, whose sum is σ = 720645428. Its totient is φ = 720645426.

The previous prime is 720645383. The next prime is 720645461. The reversal of 720645427 is 724546027.

It is a strong prime.

It is an emirp because it is prime and its reverse (724546027) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-720645427 is a prime.

It is not a weakly prime, because it can be changed into another prime (720645227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360322713 + 360322714.

It is an arithmetic number, because the mean of its divisors is an integer number (360322714).

Almost surely, 2^720645427 is an apocalyptic number.

720645427 is a deficient number, since it is larger than the sum of its proper divisors (1).

720645427 is an equidigital number, since it uses as much as digits as its factorization.

720645427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 94080, while the sum is 37.

The square root of 720645427 is about 26844.8398579690. The cubic root of 720645427 is about 896.5486859569.

The spelling of 720645427 in words is "seven hundred twenty million, six hundred forty-five thousand, four hundred twenty-seven".