261647567712620 has 288 divisors, whose sum is σ = 591774720264000. Its totient is φ = 97148391653376.

The previous prime is 261647567712617. The next prime is 261647567712679. The reversal of 261647567712620 is 26217765746162.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 111863003411 + ... + 111863005749.

It is an arithmetic number, because the mean of its divisors is an integer number (2054773334250).

Almost surely, 2^{261647567712620} is an apocalyptic number.

261647567712620 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 261647567712620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (295887360132000).

261647567712620 is an abundant number, since it is smaller than the sum of its proper divisors (330127152551380).

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

261647567712620 is a wasteful number, since it uses less digits than its factorization.

261647567712620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3397 (or 3378 counting only the distinct ones).

The product of its (nonzero) digits is 71124480, while the sum is 62.

The spelling of 261647567712620 in words is "two hundred sixty-one trillion, six hundred forty-seven billion, five hundred sixty-seven million, seven hundred twelve thousand, six hundred twenty".