6445693789 has 2 divisors, whose sum is σ = 6445693790. Its totient is φ = 6445693788.

The previous prime is 6445693781. The next prime is 6445693801. The reversal of 6445693789 is 9873965446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6441346564 + 4347225 = 80258^2 + 2085^2 .

It is a cyclic number.

It is not a de Polignac number, because 6445693789 - 2³ = 6445693781 is a prime.

It is a super-3 number, since 3×6445693789³ (a number of 30 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6445693781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3222846894 + 3222846895.

It is an arithmetic number, because the mean of its divisors is an integer number (3222846895).

Almost surely, 2^6445693789 is an apocalyptic number.

It is an amenable number.

6445693789 is a deficient number, since it is larger than the sum of its proper divisors (1).

6445693789 is an equidigital number, since it uses as much as digits as its factorization.

6445693789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 39191040, while the sum is 61.

The square root of 6445693789 is about 80285.0782462096. The cubic root of 6445693789 is about 1861.0436380157.

The spelling of 6445693789 in words is "six billion, four hundred forty-five million, six hundred ninety-three thousand, seven hundred eighty-nine".