55678999 has 2 divisors, whose sum is σ = 55679000.
Its totient is φ = 55678998.
The previous prime is 55678993. The next prime is 55679017. The reversal of 55678999 is 99987655.
It is a weak prime.
It is a cyclic number.
It is not a de Polignac number, because 55678999 - 27 = 55678871 is a prime.
It is a plaindrome in base 10.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (55678993) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27839499 + 27839500.
It is an arithmetic number, because the mean of its divisors is an integer number (27839500).
Almost surely, 255678999 is an apocalyptic number.
55678999 is a deficient number, since it is larger than the sum of its proper divisors (1).
55678999 is an equidigital number, since it uses as much as digits as its factorization.
55678999 is an evil number, because the sum of its binary digits is even.
The product of its digits is 6123600, while the sum is 58.
The square root of 55678999 is about 7461.8361681291.
The cubic root of 55678999 is about 381.8538200587.
The spelling of 55678999 in words is "fifty-five million, six hundred seventy-eight thousand, nine hundred ninety-nine".