55166521851 has 40 divisors (see below), whose sum is σ = 97220158464. Its totient is φ = 30506822640.

The previous prime is 55166521807. The next prime is 55166521889. The reversal of 55166521851 is 15812566155.

55166521851 is a `hidden beast` number, since 5 + 516 + 6 + 52 + 1 + 85 + 1 = 666.

It is not a de Polignac number, because 55166521851 - 2⁹ = 55166521339 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 55166521797 and 55166521806.

It is not an unprimeable number, because it can be changed into a prime (55166525851) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1551705 + ... + 1586858.

Almost surely, 2^55166521851 is an apocalyptic number.

55166521851 is a deficient number, since it is larger than the sum of its proper divisors (42053636613).

55166521851 is a wasteful number, since it uses less digits than its factorization.

55166521851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3138613 (or 3138604 counting only the distinct ones).

The product of its digits is 360000, while the sum is 45.

The spelling of 55166521851 in words is "fifty-five billion, one hundred sixty-six million, five hundred twenty-one thousand, eight hundred fifty-one".