261579407100 has 288 divisors, whose sum is σ = 879879684096. Its totient is φ = 59364729600.

The previous prime is 261579407093. The next prime is 261579407101. The reversal of 261579407100 is 1704975162.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261579407101) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3530637 + ... + 3603963.

It is an arithmetic number, because the mean of its divisors is an integer number (3055137792).

Almost surely, 2^261579407100 is an apocalyptic number.

261579407100 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 261579407100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (439939842048).

261579407100 is an abundant number, since it is smaller than the sum of its proper divisors (618300276996).

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

261579407100 is a wasteful number, since it uses less digits than its factorization.

261579407100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73425 (or 73418 counting only the distinct ones).

The product of its (nonzero) digits is 105840, while the sum is 42.

The spelling of 261579407100 in words is "two hundred sixty-one billion, five hundred seventy-nine million, four hundred seven thousand, one hundred".