16861391064 has 96 divisors (see below), whose sum is σ = 53600620320. Its totient is φ = 4687331328.

The previous prime is 16861390963. The next prime is 16861391077. The reversal of 16861391064 is 46019316861.

16861391064 is a `hidden beast` number, since 16 + 8 + 613 + 9 + 10 + 6 + 4 = 666.

It is a super-2 number, since 2×16861391064² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 433449 + ... + 470744.

It is an arithmetic number, because the mean of its divisors is an integer number (558339795).

Almost surely, 2^16861391064 is an apocalyptic number.

16861391064 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

16861391064 is an abundant number, since it is smaller than the sum of its proper divisors (36739229256).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16861391064 is a wasteful number, since it uses less digits than its factorization.

16861391064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 904249 (or 904242 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 16861391064 in words is "sixteen billion, eight hundred sixty-one million, three hundred ninety-one thousand, sixty-four".