261989689781120 has 1536 divisors, whose sum is σ = 800435292733440. Its totient is φ = 81503506022400.

The previous prime is 261989689781117. The next prime is 261989689781219. The reversal of 261989689781120 is 21187986989162.

261989689781120 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (77) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 360370962197 + ... + 360370962923.

It is an arithmetic number, because the mean of its divisors is an integer number (521116727040).

Almost surely, 2^{261989689781120} is an apocalyptic number.

261989689781120 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 261989689781120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (400217646366720).

261989689781120 is an abundant number, since it is smaller than the sum of its proper divisors (538445602952320).

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

261989689781120 is a wasteful number, since it uses less digits than its factorization.

261989689781120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112 (or 1093 counting only the distinct ones).

The product of its (nonzero) digits is 376233984, while the sum is 77.

The spelling of 261989689781120 in words is "two hundred sixty-one trillion, nine hundred eighty-nine billion, six hundred eighty-nine million, seven hundred eighty-one thousand, one hundred twenty".