261553237054242 has 32 divisors (see below), whose sum is σ = 606758895347712. Its totient is φ = 73614130683984.

The previous prime is 261553237054181. The next prime is 261553237054279. The reversal of 261553237054242 is 242450732355162.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46473564538 + ... + 46473570165.

It is an arithmetic number, because the mean of its divisors is an integer number (18961215479616).

Almost surely, 2^{261553237054242} is an apocalyptic number.

261553237054242 is an abundant number, since it is smaller than the sum of its proper divisors (345205658293470).

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

261553237054242 is a wasteful number, since it uses less digits than its factorization.

261553237054242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92947134782.

The product of its (nonzero) digits is 12096000, while the sum is 51.

The spelling of 261553237054242 in words is "two hundred sixty-one trillion, five hundred fifty-three billion, two hundred thirty-seven million, fifty-four thousand, two hundred forty-two".