55615993 has 12 divisors (see below), whose sum is σ = 60207732. Its totient is φ = 51196160.

The previous prime is 55615991. The next prime is 55616003. The reversal of 55615993 is 39951655.

55615993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 33965584 + 21650409 = 5828^2 + 4653^2 .

It is not a de Polignac number, because 55615993 - 2¹ = 55615991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55615991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36813 + ... + 38293.

It is an arithmetic number, because the mean of its divisors is an integer number (5017311).

Almost surely, 2^55615993 is an apocalyptic number.

It is an amenable number.

55615993 is a deficient number, since it is larger than the sum of its proper divisors (4591739).

55615993 is a wasteful number, since it uses less digits than its factorization.

55615993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1592 (or 1545 counting only the distinct ones).

The product of its digits is 182250, while the sum is 43.

The square root of 55615993 is about 7457.6130899907. The cubic root of 55615993 is about 381.7097312463.

The spelling of 55615993 in words is "fifty-five million, six hundred fifteen thousand, nine hundred ninety-three".