1620557047 has 2 divisors, whose sum is σ = 1620557048. Its totient is φ = 1620557046.

The previous prime is 1620557041. The next prime is 1620557077. The reversal of 1620557047 is 7407550261.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1620557047 - 2⁷ = 1620556919 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1620556997 and 1620557015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1620557041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810278523 + 810278524.

It is an arithmetic number, because the mean of its divisors is an integer number (810278524).

Almost surely, 2^1620557047 is an apocalyptic number.

1620557047 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620557047 is an equidigital number, since it uses as much as digits as its factorization.

1620557047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58800, while the sum is 37.

The square root of 1620557047 is about 40256.1429722223. The cubic root of 1620557047 is about 1174.5948920646.

The spelling of 1620557047 in words is "one billion, six hundred twenty million, five hundred fifty-seven thousand, forty-seven".