261867720708 has 36 divisors (see below), whose sum is σ = 722120079408. Its totient is φ = 79353854640.

The previous prime is 261867720703. The next prime is 261867720781. The reversal of 261867720708 is 807027768162.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (261867720703) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 330640666 + ... + 330641457.

Almost surely, 2^261867720708 is an apocalyptic number.

It is an amenable number.

261867720708 is an abundant number, since it is smaller than the sum of its proper divisors (460252358700).

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

261867720708 is a wasteful number, since it uses less digits than its factorization.

261867720708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661282144 (or 661282139 counting only the distinct ones).

The product of its (nonzero) digits is 3161088, while the sum is 54.

The spelling of 261867720708 in words is "two hundred sixty-one billion, eight hundred sixty-seven million, seven hundred twenty thousand, seven hundred eight".