1657985479 has 2 divisors, whose sum is σ = 1657985480. Its totient is φ = 1657985478.

The previous prime is 1657985471. The next prime is 1657985509. The reversal of 1657985479 is 9745897561.

It is a weak prime.

It is an emirp because it is prime and its reverse (9745897561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1657985479 - 2³ = 1657985471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1657985471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 828992739 + 828992740.

It is an arithmetic number, because the mean of its divisors is an integer number (828992740).

Almost surely, 2^1657985479 is an apocalyptic number.

1657985479 is a deficient number, since it is larger than the sum of its proper divisors (1).

1657985479 is an equidigital number, since it uses as much as digits as its factorization.

1657985479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19051200, while the sum is 61.

The square root of 1657985479 is about 40718.3678332027. The cubic root of 1657985479 is about 1183.5689797894.

The spelling of 1657985479 in words is "one billion, six hundred fifty-seven million, nine hundred eighty-five thousand, four hundred seventy-nine".