1621989089 has 16 divisors (see below), whose sum is σ = 1879078656. Its totient is φ = 1371340800.

The previous prime is 1621989077. The next prime is 1621989097. The reversal of 1621989089 is 9809891261.

It is a cyclic number.

It is not a de Polignac number, because 1621989089 - 2⁸ = 1621988833 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1621989089.

It is not an unprimeable number, because it can be changed into a prime (1621989029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 207329 + ... + 215009.

It is an arithmetic number, because the mean of its divisors is an integer number (117442416).

Almost surely, 2^1621989089 is an apocalyptic number.

It is an amenable number.

1621989089 is a deficient number, since it is larger than the sum of its proper divisors (257089567).

1621989089 is an equidigital number, since it uses as much as digits as its factorization.

1621989089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8096.

The product of its (nonzero) digits is 559872, while the sum is 53.

The square root of 1621989089 is about 40273.9256715806. The cubic root of 1621989089 is about 1174.9407760100.

The spelling of 1621989089 in words is "one billion, six hundred twenty-one million, nine hundred eighty-nine thousand, eighty-nine".