6400019545 has 4 divisors (see below), whose sum is σ = 7680023460. Its totient is φ = 5120015632.

The previous prime is 6400019503. The next prime is 6400019557. The reversal of 6400019545 is 5459100046.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5459100046 = 2 ⋅2729550023.

It can be written as a sum of positive squares in 2 ways, for example, as 1888076304 + 4511943241 = 43452^2 + 67171^2 .

It is a cyclic number.

It is not a de Polignac number, because 6400019545 - 2¹⁵ = 6399986777 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6400019545.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 640001950 + ... + 640001959.

It is an arithmetic number, because the mean of its divisors is an integer number (1920005865).

Almost surely, 2^6400019545 is an apocalyptic number.

It is an amenable number.

6400019545 is a deficient number, since it is larger than the sum of its proper divisors (1280003915).

6400019545 is a wasteful number, since it uses less digits than its factorization.

6400019545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280003914.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 6400019545 is about 80000.1221561567. The cubic root of 6400019545 is about 1856.6374234401.

The spelling of 6400019545 in words is "six billion, four hundred million, nineteen thousand, five hundred forty-five".