261424747864 has 96 divisors (see below), whose sum is σ = 600887160000. Its totient is φ = 106022613312.

The previous prime is 261424747853. The next prime is 261424747879. The reversal of 261424747864 is 468747424162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6735987 + ... + 6774685.

It is an arithmetic number, because the mean of its divisors is an integer number (6259241250).

Almost surely, 2^261424747864 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 261424747864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (300443580000).

261424747864 is an abundant number, since it is smaller than the sum of its proper divisors (339462412136).

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

261424747864 is a wasteful number, since it uses less digits than its factorization.

261424747864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39645 (or 39634 counting only the distinct ones).

The product of its digits is 14450688, while the sum is 55.

The spelling of 261424747864 in words is "two hundred sixty-one billion, four hundred twenty-four million, seven hundred forty-seven thousand, eight hundred sixty-four".