981888639345 has 12 divisors (see below), whose sum is σ = 1701940308276. Its totient is φ = 523673940960.

The previous prime is 981888639323. The next prime is 981888639349. The reversal of 981888639345 is 543936888189.

981888639345 is a `hidden beast` number, since 9 + 81 + 88 + 86 + 393 + 4 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 636483244401 + 345405394944 = 797799^2 + 587712^2 .

It is not a de Polignac number, because 981888639345 - 2¹³ = 981888631153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (981888639349) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10909873726 + ... + 10909873815.

It is an arithmetic number, because the mean of its divisors is an integer number (141828359023).

Almost surely, 2^981888639345 is an apocalyptic number.

It is an amenable number.

981888639345 is a deficient number, since it is larger than the sum of its proper divisors (720051668931).

981888639345 is a wasteful number, since it uses less digits than its factorization.

981888639345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21819747552 (or 21819747549 counting only the distinct ones).

The product of its digits is 358318080, while the sum is 72.

The spelling of 981888639345 in words is "nine hundred eighty-one billion, eight hundred eighty-eight million, six hundred thirty-nine thousand, three hundred forty-five".