6511121545 has 4 divisors (see below), whose sum is σ = 7813345860. Its totient is φ = 5208897232.

The previous prime is 6511121503. The next prime is 6511121569. The reversal of 6511121545 is 5451211156.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 716258169 + 5794863376 = 26763^2 + 76124^2 .

It is a cyclic number.

It is not a de Polignac number, because 6511121545 - 2¹⁹ = 6510597257 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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, 651112150 + ... + 651112159.

It is an arithmetic number, because the mean of its divisors is an integer number (1953336465).

Almost surely, 2^6511121545 is an apocalyptic number.

It is an amenable number.

6511121545 is a deficient number, since it is larger than the sum of its proper divisors (1302224315).

6511121545 is a wasteful number, since it uses less digits than its factorization.

6511121545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1302224314.

The product of its digits is 6000, while the sum is 31.

The square root of 6511121545 is about 80691.5208990387. The cubic root of 6511121545 is about 1867.3193639959.

The spelling of 6511121545 in words is "six billion, five hundred eleven million, one hundred twenty-one thousand, five hundred forty-five".