261193011264 has 112 divisors (see below), whose sum is σ = 784196755200. Its totient is φ = 85211877888.

The previous prime is 261193011257. The next prime is 261193011281. The reversal of 261193011264 is 462110391162.

It is a happy number.

261193011264 is a `hidden beast` number, since 2 + 611 + 9 + 3 + 0 + 11 + 26 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1526799 + ... + 1689230.

Almost surely, 2^261193011264 is an apocalyptic number.

261193011264 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

261193011264 is an abundant number, since it is smaller than the sum of its proper divisors (523003743936).

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

261193011264 is a wasteful number, since it uses less digits than its factorization.

261193011264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3216097 (or 3216081 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The spelling of 261193011264 in words is "two hundred sixty-one billion, one hundred ninety-three million, eleven thousand, two hundred sixty-four".