261204740 has 48 divisors (see below), whose sum is σ = 575527680. Its totient is φ = 99442560.

The previous prime is 261204737. The next prime is 261204743. The reversal of 261204740 is 47402162.

It is an interprime number because it is at equal distance from previous prime (261204737) and next prime (261204743).

It is not an unprimeable number, because it can be changed into a prime (261204743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38009 + ... + 44351.

It is an arithmetic number, because the mean of its divisors is an integer number (11990160).

Almost surely, 2^261204740 is an apocalyptic number.

261204740 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 261204740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287763840).

261204740 is an abundant number, since it is smaller than the sum of its proper divisors (314322940).

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

261204740 is a wasteful number, since it uses less digits than its factorization.

261204740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6452 (or 6450 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 261204740 is about 16161.8297231471. The cubic root of 261204740 is about 639.2347135209.

The spelling of 261204740 in words is "two hundred sixty-one million, two hundred four thousand, seven hundred forty".