1621189663 has 2 divisors, whose sum is σ = 1621189664. Its totient is φ = 1621189662.

The previous prime is 1621189627. The next prime is 1621189709. The reversal of 1621189663 is 3669811261.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1621189663 - 2²⁹ = 1084318751 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1621189613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810594831 + 810594832.

It is an arithmetic number, because the mean of its divisors is an integer number (810594832).

Almost surely, 2^1621189663 is an apocalyptic number.

1621189663 is a deficient number, since it is larger than the sum of its proper divisors (1).

1621189663 is an equidigital number, since it uses as much as digits as its factorization.

1621189663 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 43.

The square root of 1621189663 is about 40263.9995902046. Note that the first 3 decimals coincide. The cubic root of 1621189663 is about 1174.7477141769.

The spelling of 1621189663 in words is "one billion, six hundred twenty-one million, one hundred eighty-nine thousand, six hundred sixty-three".