55121221607 has 4 divisors (see below), whose sum is σ = 55122655176. Its totient is φ = 55119788040.

The previous prime is 55121221567. The next prime is 55121221621. The reversal of 55121221607 is 70612212155.

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 55121221607 - 2¹⁶ = 55121156071 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 (55121221637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 657473 + ... + 736554.

It is an arithmetic number, because the mean of its divisors is an integer number (13780663794).

Almost surely, 2^55121221607 is an apocalyptic number.

55121221607 is a deficient number, since it is larger than the sum of its proper divisors (1433569).

55121221607 is a wasteful number, since it uses less digits than its factorization.

55121221607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1433568.

The product of its (nonzero) digits is 8400, while the sum is 32.

The spelling of 55121221607 in words is "fifty-five billion, one hundred twenty-one million, two hundred twenty-one thousand, six hundred seven".