55861999 has 2 divisors, whose sum is σ = 55862000. Its totient is φ = 55861998.

The previous prime is 55861951. The next prime is 55862011. The reversal of 55861999 is 99916855.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 55861999 - 2¹³ = 55853807 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55861199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27930999 + 27931000.

It is an arithmetic number, because the mean of its divisors is an integer number (27931000).

Almost surely, 2^55861999 is an apocalyptic number.

55861999 is a deficient number, since it is larger than the sum of its proper divisors (1).

55861999 is an equidigital number, since it uses as much as digits as its factorization.

55861999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 874800, while the sum is 52.

The square root of 55861999 is about 7474.0885062996. The cubic root of 55861999 is about 382.2717085056.

The spelling of 55861999 in words is "fifty-five million, eight hundred sixty-one thousand, nine hundred ninety-nine".