261329472 has 84 divisors (see below), whose sum is σ = 758667520. Its totient is φ = 85992192.

The previous prime is 261329459. The next prime is 261329479. The reversal of 261329472 is 274923162.

261329472 is a `hidden beast` number, since 261 + 329 + 4 + 72 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (261329479) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42633 + ... + 48375.

Almost surely, 2^261329472 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 261329472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (379333760).

261329472 is an abundant number, since it is smaller than the sum of its proper divisors (497338048).

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

261329472 is a wasteful number, since it uses less digits than its factorization.

261329472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5840 (or 5827 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 261329472 is about 16165.6881078412. The cubic root of 261329472 is about 639.3364476831.

The spelling of 261329472 in words is "two hundred sixty-one million, three hundred twenty-nine thousand, four hundred seventy-two".