261553305445145 has 16 divisors (see below), whose sum is σ = 366022118409600. Its totient is φ = 179350838018352.

The previous prime is 261553305445141. The next prime is 261553305445169. The reversal of 261553305445145 is 541544503355162.

It is not a de Polignac number, because 261553305445145 - 2² = 261553305445141 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261553305445141) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76254606287 + ... + 76254609716.

It is an arithmetic number, because the mean of its divisors is an integer number (22876382400600).

Almost surely, 2^{261553305445145} is an apocalyptic number.

It is an amenable number.

261553305445145 is a deficient number, since it is larger than the sum of its proper divisors (104468812964455).

261553305445145 is an equidigital number, since it uses as much as digits as its factorization.

261553305445145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152509216029 (or 152509216015 counting only the distinct ones).

The product of its (nonzero) digits is 21600000, while the sum is 53.

The spelling of 261553305445145 in words is "two hundred sixty-one trillion, five hundred fifty-three billion, three hundred five million, four hundred forty-five thousand, one hundred forty-five".