6421505145 has 32 divisors (see below), whose sum is σ = 11798369280. Its totient is φ = 2949589440.

The previous prime is 6421505117. The next prime is 6421505179. The reversal of 6421505145 is 5415051246.

6421505145 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6421505145 - 2⁷ = 6421505017 is a prime.

It is a super-2 number, since 2×6421505145² = 82471456654522942050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1021029 + ... + 1027298.

It is an arithmetic number, because the mean of its divisors is an integer number (368699040).

Almost surely, 2^6421505145 is an apocalyptic number.

It is an amenable number.

6421505145 is a deficient number, since it is larger than the sum of its proper divisors (5376864135).

6421505145 is a wasteful number, since it uses less digits than its factorization.

6421505145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2048365.

The product of its (nonzero) digits is 24000, while the sum is 33.

The square root of 6421505145 is about 80134.2944375253. The cubic root of 6421505145 is about 1858.7127510905.

It can be divided in two parts, 6421 and 505145, that added together give a triangular number (511566 = T₁₀₁₁).

The spelling of 6421505145 in words is "six billion, four hundred twenty-one million, five hundred five thousand, one hundred forty-five".