261019100160 has 704 divisors, whose sum is σ = 1141734720000. Its totient is φ = 55069507584.

The previous prime is 261019100149. The next prime is 261019100161. The reversal of 261019100160 is 61001910162.

It is a super-2 number, since 2×261019100160² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (261019100161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12569466 + ... + 12590214.

Almost surely, 2^261019100160 is an apocalyptic number.

261019100160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261019100160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (570867360000).

261019100160 is an abundant number, since it is smaller than the sum of its proper divisors (880715619840).

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

261019100160 is a wasteful number, since it uses less digits than its factorization.

261019100160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20803 (or 20779 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

The spelling of 261019100160 in words is "two hundred sixty-one billion, nineteen million, one hundred thousand, one hundred sixty".