261657146725555 has 8 divisors (see below), whose sum is σ = 358844086937952. Its totient is φ = 179422043468928.

The previous prime is 261657146725501. The next prime is 261657146725571. The reversal of 261657146725555 is 555527641756162.

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 261657146725555 - 2¹⁵ = 261657146692787 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3737959238902 + ... + 3737959238971.

It is an arithmetic number, because the mean of its divisors is an integer number (44855510867244).

Almost surely, 2^{261657146725555} is an apocalyptic number.

261657146725555 is a deficient number, since it is larger than the sum of its proper divisors (97186940212397).

261657146725555 is an equidigital number, since it uses as much as digits as its factorization.

261657146725555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7475918477885.

The product of its digits is 529200000, while the sum is 67.

The spelling of 261657146725555 in words is "two hundred sixty-one trillion, six hundred fifty-seven billion, one hundred forty-six million, seven hundred twenty-five thousand, five hundred fifty-five".