261654519168 has 192 divisors, whose sum is σ = 911118892320. Its totient is φ = 70360842240.

The previous prime is 261654519127. The next prime is 261654519169. The reversal of 261654519168 is 861915456162.

It is a happy number.

261654519168 is a `hidden beast` number, since 2 + 6 + 1 + 6 + 545 + 1 + 91 + 6 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261654519169) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 817243 + ... + 1091418.

Almost surely, 2^261654519168 is an apocalyptic number.

261654519168 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

261654519168 is an abundant number, since it is smaller than the sum of its proper divisors (649464373152).

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

261654519168 is a wasteful number, since it uses less digits than its factorization.

261654519168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1908705 (or 1908690 counting only the distinct ones).

The product of its digits is 3110400, while the sum is 54.

The spelling of 261654519168 in words is "two hundred sixty-one billion, six hundred fifty-four million, five hundred nineteen thousand, one hundred sixty-eight".