55521571551 has 32 divisors (see below), whose sum is σ = 76585098240. Its totient is φ = 35757473664.

The previous prime is 55521571507. The next prime is 55521571561. The reversal of 55521571551 is 15517512555.

It is not a de Polignac number, because 55521571551 - 2¹⁸ = 55521309407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55521571561) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24212361 + ... + 24214653.

It is an arithmetic number, because the mean of its divisors is an integer number (2393284320).

Almost surely, 2^55521571551 is an apocalyptic number.

55521571551 is a deficient number, since it is larger than the sum of its proper divisors (21063526689).

55521571551 is a wasteful number, since it uses less digits than its factorization.

55521571551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4495.

The product of its digits is 218750, while the sum is 42.

The spelling of 55521571551 in words is "fifty-five billion, five hundred twenty-one million, five hundred seventy-one thousand, five hundred fifty-one".