55661611501 has 2 divisors, whose sum is σ = 55661611502. Its totient is φ = 55661611500.

The previous prime is 55661611471. The next prime is 55661611547. The reversal of 55661611501 is 10511616655.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40632077476 + 15029534025 = 201574^2 + 122595^2 .

It is a cyclic number.

It is not a de Polignac number, because 55661611501 - 2⁵ = 55661611469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55661611571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27830805750 + 27830805751.

It is an arithmetic number, because the mean of its divisors is an integer number (27830805751).

Almost surely, 2^55661611501 is an apocalyptic number.

It is an amenable number.

55661611501 is a deficient number, since it is larger than the sum of its proper divisors (1).

55661611501 is an equidigital number, since it uses as much as digits as its factorization.

55661611501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27000, while the sum is 37.

The spelling of 55661611501 in words is "fifty-five billion, six hundred sixty-one million, six hundred eleven thousand, five hundred one".