55638477432661 has 2 divisors, whose sum is σ = 55638477432662. Its totient is φ = 55638477432660.

The previous prime is 55638477432617. The next prime is 55638477432667. The reversal of 55638477432661 is 16623477483655.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52979197099761 + 2659280332900 = 7278681^2 + 1630730^2 .

It is a cyclic number.

It is not a de Polignac number, because 55638477432661 - 2⁹ = 55638477432149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55638477432667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27819238716330 + 27819238716331.

It is an arithmetic number, because the mean of its divisors is an integer number (27819238716331).

Almost surely, 2^{55638477432661} is an apocalyptic number.

It is an amenable number.

55638477432661 is a deficient number, since it is larger than the sum of its proper divisors (1).

55638477432661 is an equidigital number, since it uses as much as digits as its factorization.

55638477432661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 609638400, while the sum is 67.

The spelling of 55638477432661 in words is "fifty-five trillion, six hundred thirty-eight billion, four hundred seventy-seven million, four hundred thirty-two thousand, six hundred sixty-one".