261993572057296 has 80 divisors (see below), whose sum is σ = 536305536748800. Its totient is φ = 123784808845824.

The previous prime is 261993572057233. The next prime is 261993572057297. The reversal of 261993572057296 is 692750275399162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261993572057297) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 789916231 + ... + 790247833.

It is an arithmetic number, because the mean of its divisors is an integer number (6703819209360).

Almost surely, 2^{261993572057296} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261993572057296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268152768374400).

261993572057296 is an abundant number, since it is smaller than the sum of its proper divisors (274311964691504).

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

261993572057296 is a wasteful number, since it uses less digits than its factorization.

261993572057296 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367916 (or 367910 counting only the distinct ones).

The product of its (nonzero) digits is 771573600, while the sum is 73.

The spelling of 261993572057296 in words is "two hundred sixty-one trillion, nine hundred ninety-three billion, five hundred seventy-two million, fifty-seven thousand, two hundred ninety-six".