6420555155 has 16 divisors (see below), whose sum is σ = 9323294400. Its totient is φ = 4143685632.

The previous prime is 6420555149. The next prime is 6420555181. The reversal of 6420555155 is 5515550246.

It is a cyclic number.

It is not a de Polignac number, because 6420555155 - 2³⁰ = 5346813331 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5394830 + ... + 5396019.

It is an arithmetic number, because the mean of its divisors is an integer number (582705900).

Almost surely, 2^6420555155 is an apocalyptic number.

6420555155 is a deficient number, since it is larger than the sum of its proper divisors (2902739245).

6420555155 is a wasteful number, since it uses less digits than its factorization.

6420555155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10790878.

The product of its (nonzero) digits is 150000, while the sum is 38.

The square root of 6420555155 is about 80128.3667311396. The cubic root of 6420555155 is about 1858.6210879696.

The spelling of 6420555155 in words is "six billion, four hundred twenty million, five hundred fifty-five thousand, one hundred fifty-five".