781425944289 has 27 divisors (see below), whose sum is σ = 1199096839993. Its totient is φ = 490278187392.

The previous prime is 781425944269. The next prime is 781425944317. The reversal of 781425944289 is 982449524187.

The square root of 781425944289 is 883983.

It is a perfect power (a square), and thus also a powerful number.

781425944289 is a `hidden beast` number, since 7 + 8 + 1 + 425 + 94 + 42 + 89 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 53168519889 + 728257424400 = 230583^2 + 853380^2 .

It is not a de Polignac number, because 781425944289 - 2¹³ = 781425936097 is a prime.

It is a super-2 number, since 2×781425944289² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (781425944209) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 45074467 + ... + 45091799.

Almost surely, 2^781425944289 is an apocalyptic number.

781425944289 is the 883983-rd square number.

781425944289 is the 441992-nd centered octagonal number.

It is an amenable number.

781425944289 is a deficient number, since it is larger than the sum of its proper divisors (417670895704).

781425944289 is an frugal number, since it uses more digits than its factorization.

781425944289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34706 (or 17353 counting only the distinct ones).

The product of its digits is 46448640, while the sum is 63.

The spelling of 781425944289 in words is "seven hundred eighty-one billion, four hundred twenty-five million, nine hundred forty-four thousand, two hundred eighty-nine".