55007019921 has 32 divisors (see below), whose sum is σ = 84192768000. Its totient is φ = 31293036864.

The previous prime is 55007019917. The next prime is 55007019923. The reversal of 55007019921 is 12991070055.

It is not a de Polignac number, because 55007019921 - 2² = 55007019917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 55007019921.

It is not an unprimeable number, because it can be changed into a prime (55007019923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15180916 + ... + 15184538.

It is an arithmetic number, because the mean of its divisors is an integer number (2631024000).

Almost surely, 2^55007019921 is an apocalyptic number.

It is an amenable number.

55007019921 is a deficient number, since it is larger than the sum of its proper divisors (29185748079).

55007019921 is a wasteful number, since it uses less digits than its factorization.

55007019921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6645.

The product of its (nonzero) digits is 28350, while the sum is 39.

Adding to 55007019921 its reverse (12991070055), we get a palindrome (67998089976).

The spelling of 55007019921 in words is "fifty-five billion, seven million, nineteen thousand, nine hundred twenty-one".