55770809 has 2 divisors, whose sum is σ = 55770810. Its totient is φ = 55770808.

The previous prime is 55770797. The next prime is 55770817. The reversal of 55770809 is 90807755.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31956409 + 23814400 = 5653^2 + 4880^2 .

It is a cyclic number.

It is not a de Polignac number, because 55770809 - 2²⁰ = 54722233 is a prime.

It is a super-2 number, since 2×55770809² = 6220766273028962, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (55770899) 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, 27885404 + 27885405.

It is an arithmetic number, because the mean of its divisors is an integer number (27885405).

Almost surely, 2^55770809 is an apocalyptic number.

It is an amenable number.

55770809 is a deficient number, since it is larger than the sum of its proper divisors (1).

55770809 is an equidigital number, since it uses as much as digits as its factorization.

55770809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 88200, while the sum is 41.

The square root of 55770809 is about 7467.9856052352. The cubic root of 55770809 is about 382.0635864473.

The spelling of 55770809 in words is "fifty-five million, seven hundred seventy thousand, eight hundred nine".