6444628155 has 24 divisors (see below), whose sum is σ = 12766502112. Its totient is φ = 2946115584.

The previous prime is 6444628123. The next prime is 6444628187. The reversal of 6444628155 is 5518264446.

It is a happy number.

6444628155 is a `hidden beast` number, since 6 + 4 + 4 + 4 + 628 + 15 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (6444628123) and next prime (6444628187).

It is not a de Polignac number, because 6444628155 - 2⁵ = 6444628123 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 6444628155.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10229254 + ... + 10229883.

It is an arithmetic number, because the mean of its divisors is an integer number (531937588).

Almost surely, 2^6444628155 is an apocalyptic number.

6444628155 is a deficient number, since it is larger than the sum of its proper divisors (6321873957).

6444628155 is a wasteful number, since it uses less digits than its factorization.

6444628155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20459155 (or 20459152 counting only the distinct ones).

The product of its digits is 921600, while the sum is 45.

The square root of 6444628155 is about 80278.4414086372. The cubic root of 6444628155 is about 1860.9410733815.

The spelling of 6444628155 in words is "six billion, four hundred forty-four million, six hundred twenty-eight thousand, one hundred fifty-five".