261421344 has 72 divisors (see below), whose sum is σ = 770973840. Its totient is φ = 87137856.

The previous prime is 261421343. The next prime is 261421351. The reversal of 261421344 is 443124162.

It is a happy number.

261421344 is a `hidden beast` number, since 2 + 614 + 2 + 1 + 3 + 44 = 666.

261421344 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 (72).

It is a super-2 number, since 2×261421344² = 136682238197532672, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (261421343) 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, 9034 + ... + 24585.

It is an arithmetic number, because the mean of its divisors is an integer number (10707970).

Almost surely, 2^261421344 is an apocalyptic number.

261421344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

261421344 is an abundant number, since it is smaller than the sum of its proper divisors (509552496).

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

261421344 is an equidigital number, since it uses as much as digits as its factorization.

261421344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33644 (or 33624 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

The square root of 261421344 is about 16168.5294322025. The cubic root of 261421344 is about 639.4113598057.

The spelling of 261421344 in words is "two hundred sixty-one million, four hundred twenty-one thousand, three hundred forty-four".