55791616 has 52 divisors (see below), whose sum is σ = 114117012. Its totient is φ = 27262976.

The previous prime is 55791613. The next prime is 55791623. The reversal of 55791616 is 61619755.

It can be written as a sum of positive squares in 2 ways, for example, as 49561600 + 6230016 = 7040^2 + 2496^2 .

It is a super-2 number, since 2×55791616² = 6225408831782912, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55791613) 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, 216960 + ... + 217216.

Almost surely, 2^55791616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55791616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57058506).

55791616 is an abundant number, since it is smaller than the sum of its proper divisors (58325396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55791616 is an equidigital number, since it uses as much as digits as its factorization.

55791616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334 (or 312 counting only the distinct ones).

The product of its digits is 56700, while the sum is 40.

The square root of 55791616 is about 7469.3785551410. The cubic root of 55791616 is about 382.1110940280. Note that the first 3 decimals are identical.

The spelling of 55791616 in words is "fifty-five million, seven hundred ninety-one thousand, six hundred sixteen".