261023880 has 192 divisors, whose sum is σ = 865926720. Its totient is φ = 62899200.

The previous prime is 261023869. The next prime is 261023891. The reversal of 261023880 is 88320162.

261023880 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (261023869) and next prime (261023891).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1236975 + ... + 1237185.

It is an arithmetic number, because the mean of its divisors is an integer number (4510035).

Almost surely, 2^261023880 is an apocalyptic number.

261023880 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 261023880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (432963360).

261023880 is an abundant number, since it is smaller than the sum of its proper divisors (604902840).

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

261023880 is a wasteful number, since it uses less digits than its factorization.

261023880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312 (or 295 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 261023880 is about 16156.2334719451. The cubic root of 261023880 is about 639.0871425847.

The spelling of 261023880 in words is "two hundred sixty-one million, twenty-three thousand, eight hundred eighty".