16863359881 has 27 divisors (see below), whose sum is σ = 17978397069. Its totient is φ = 15816826200.

The previous prime is 16863359839. The next prime is 16863359911. The reversal of 16863359881 is 18895336861.

The square root of 16863359881 is 129859.

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

It is not a de Polignac number, because 16863359881 - 2²¹ = 16861262729 is a prime.

It is a super-2 number, since 2×16863359881² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16863359801) 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, 237512076 + ... + 237512146.

Almost surely, 2^16863359881 is an apocalyptic number.

16863359881 is the 129859-th square number.

16863359881 is the 64930-th centered octagonal number.

It is an amenable number.

16863359881 is a deficient number, since it is larger than the sum of its proper divisors (1115037188).

16863359881 is an frugal number, since it uses more digits than its factorization.

16863359881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322 (or 161 counting only the distinct ones).

The product of its digits is 7464960, while the sum is 58.

The spelling of 16863359881 in words is "sixteen billion, eight hundred sixty-three million, three hundred fifty-nine thousand, eight hundred eighty-one".