261221380153 has 8 divisors (see below), whose sum is σ = 272584843776. Its totient is φ = 249858417600.

The previous prime is 261221380151. The next prime is 261221380159. The reversal of 261221380153 is 351083122162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261221380153 - 2¹ = 261221380151 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261221380151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1271608 + ... + 1462678.

It is an arithmetic number, because the mean of its divisors is an integer number (34073105472).

Almost surely, 2^261221380153 is an apocalyptic number.

261221380153 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

261221380153 is a deficient number, since it is larger than the sum of its proper divisors (11363463623).

261221380153 is a wasteful number, since it uses less digits than its factorization.

261221380153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250535.

The product of its (nonzero) digits is 17280, while the sum is 34.

The spelling of 261221380153 in words is "two hundred sixty-one billion, two hundred twenty-one million, three hundred eighty thousand, one hundred fifty-three".