1620465563 has 2 divisors, whose sum is σ = 1620465564. Its totient is φ = 1620465562.

The previous prime is 1620465547. The next prime is 1620465571. The reversal of 1620465563 is 3655640261.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1620465563 - 2⁴ = 1620465547 is a prime.

It is not a weakly prime, because it can be changed into another prime (1620465533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810232781 + 810232782.

It is an arithmetic number, because the mean of its divisors is an integer number (810232782).

Almost surely, 2^1620465563 is an apocalyptic number.

1620465563 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620465563 is an equidigital number, since it uses as much as digits as its factorization.

1620465563 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 129600, while the sum is 38.

The square root of 1620465563 is about 40255.0066823991. The cubic root of 1620465563 is about 1174.5727888293.

The spelling of 1620465563 in words is "one billion, six hundred twenty million, four hundred sixty-five thousand, five hundred sixty-three".