1625720449 has 2 divisors, whose sum is σ = 1625720450. Its totient is φ = 1625720448.

The previous prime is 1625720347. The next prime is 1625720471. The reversal of 1625720449 is 9440275261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1170666225 + 455054224 = 34215^2 + 21332^2 .

It is a cyclic number.

It is not a de Polignac number, because 1625720449 - 2²³ = 1617331841 is a prime.

It is not a weakly prime, because it can be changed into another prime (1625720849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 812860224 + 812860225.

It is an arithmetic number, because the mean of its divisors is an integer number (812860225).

Almost surely, 2^1625720449 is an apocalyptic number.

It is an amenable number.

1625720449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1625720449 is an equidigital number, since it uses as much as digits as its factorization.

1625720449 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 1625720449 is about 40320.2238213034. The cubic root of 1625720449 is about 1175.8410634949.

The spelling of 1625720449 in words is "one billion, six hundred twenty-five million, seven hundred twenty thousand, four hundred forty-nine".