6420155 has 16 divisors (see below), whose sum is σ = 8973504. Its totient is φ = 4318080.

The previous prime is 6420109. The next prime is 6420173. The reversal of 6420155 is 5510246.

It is not a de Polignac number, because 6420155 - 2⁸ = 6419899 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6420155.

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, 125 + ... + 3585.

It is an arithmetic number, because the mean of its divisors is an integer number (560844).

Almost surely, 2^6420155 is an apocalyptic number.

6420155 is a deficient number, since it is larger than the sum of its proper divisors (2553349).

6420155 is a wasteful number, since it uses less digits than its factorization.

6420155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3526.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 6420155 is about 2533.8024784896. The cubic root of 6420155 is about 185.8582474903.

Subtracting from 6420155 its reverse (5510246), we obtain a palindrome (909909).

The spelling of 6420155 in words is "six million, four hundred twenty thousand, one hundred fifty-five".