55978696649 has 2 divisors, whose sum is σ = 55978696650. Its totient is φ = 55978696648.

The previous prime is 55978696601. The next prime is 55978696729. The reversal of 55978696649 is 94669687955.

55978696649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43783470025 + 12195226624 = 209245^2 + 110432^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55978696649 is a prime.

It is a super-2 number, since 2×55978696649² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (55978996649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27989348324 + 27989348325.

It is an arithmetic number, because the mean of its divisors is an integer number (27989348325).

Almost surely, 2^55978696649 is an apocalyptic number.

It is an amenable number.

55978696649 is a deficient number, since it is larger than the sum of its proper divisors (1).

55978696649 is an equidigital number, since it uses as much as digits as its factorization.

55978696649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 881798400, while the sum is 74.

The spelling of 55978696649 in words is "fifty-five billion, nine hundred seventy-eight million, six hundred ninety-six thousand, six hundred forty-nine".