261513459900 has 1152 divisors, whose sum is σ = 1128947742720. Its totient is φ = 50264064000.

The previous prime is 261513459887. The next prime is 261513459971. The reversal of 261513459900 is 9954315162.

261513459900 is a `hidden beast` number, since 2 + 6 + 1 + 51 + 3 + 4 + 599 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 215591694 + ... + 215592906.

It is an arithmetic number, because the mean of its divisors is an integer number (979989360).

Almost surely, 2^261513459900 is an apocalyptic number.

261513459900 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 261513459900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (564473871360).

261513459900 is an abundant number, since it is smaller than the sum of its proper divisors (867434282820).

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

261513459900 is a wasteful number, since it uses less digits than its factorization.

261513459900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1332 (or 1319 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 45.

The spelling of 261513459900 in words is "two hundred sixty-one billion, five hundred thirteen million, four hundred fifty-nine thousand, nine hundred".