55809779 has 4 divisors (see below), whose sum is σ = 55839960. Its totient is φ = 55779600.

The previous prime is 55809773. The next prime is 55809839. The reversal of 55809779 is 97790855.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 55809779 - 2¹² = 55805683 is a prime.

It is a super-2 number, since 2×55809779² = 6229462864057682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55809773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12122 + ... + 16079.

It is an arithmetic number, because the mean of its divisors is an integer number (13959990).

Almost surely, 2^55809779 is an apocalyptic number.

55809779 is a deficient number, since it is larger than the sum of its proper divisors (30181).

55809779 is a wasteful number, since it uses less digits than its factorization.

55809779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30180.

The product of its (nonzero) digits is 793800, while the sum is 50.

The square root of 55809779 is about 7470.5942869359. The cubic root of 55809779 is about 382.1525550413.

The spelling of 55809779 in words is "fifty-five million, eight hundred nine thousand, seven hundred seventy-nine".