261408672 has 144 divisors (see below), whose sum is σ = 857106432. Its totient is φ = 74027520.

The previous prime is 261408659. The next prime is 261408683. The reversal of 261408672 is 276804162.

261408672 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 255522 + ... + 256542.

It is an arithmetic number, because the mean of its divisors is an integer number (5952128).

Almost surely, 2^261408672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261408672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (428553216).

261408672 is an abundant number, since it is smaller than the sum of its proper divisors (595697760).

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

261408672 is a wasteful number, since it uses less digits than its factorization.

261408672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1171 (or 1160 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 261408672 is about 16168.1375550804. The cubic root of 261408672 is about 639.4010281427.

The spelling of 261408672 in words is "two hundred sixty-one million, four hundred eight thousand, six hundred seventy-two".