6461187665257 has 32 divisors (see below), whose sum is σ = 7077693313152. Its totient is φ = 5862655977984.

The previous prime is 6461187665209. The next prime is 6461187665291. The reversal of 6461187665257 is 7525667811646.

It is a de Polignac number, because none of the positive numbers 2^k-6461187665257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6461187665657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 511284943 + ... + 511297579.

It is an arithmetic number, because the mean of its divisors is an integer number (221177916036).

Almost surely, 2^{6461187665257} is an apocalyptic number.

It is an amenable number.

6461187665257 is a deficient number, since it is larger than the sum of its proper divisors (616505647895).

6461187665257 is a wasteful number, since it uses less digits than its factorization.

6461187665257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15577.

The product of its digits is 101606400, while the sum is 64.

The spelling of 6461187665257 in words is "six trillion, four hundred sixty-one billion, one hundred eighty-seven million, six hundred sixty-five thousand, two hundred fifty-seven".