55561139 has 2 divisors, whose sum is σ = 55561140. Its totient is φ = 55561138.

The previous prime is 55561043. The next prime is 55561147. The reversal of 55561139 is 93116555.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 55561139 - 2¹² = 55557043 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 55561099 and 55561108.

It is not a weakly prime, because it can be changed into another prime (55561159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27780569 + 27780570.

It is an arithmetic number, because the mean of its divisors is an integer number (27780570).

Almost surely, 2^55561139 is an apocalyptic number.

55561139 is a deficient number, since it is larger than the sum of its proper divisors (1).

55561139 is an equidigital number, since it uses as much as digits as its factorization.

55561139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20250, while the sum is 35.

The square root of 55561139 is about 7453.9344644288. The cubic root of 55561139 is about 381.5841966530.

The spelling of 55561139 in words is "fifty-five million, five hundred sixty-one thousand, one hundred thirty-nine".