6261128051661 has 40 divisors (see below), whose sum is σ = 10792970824064. Its totient is φ = 3543051624480.

The previous prime is 6261128051657. The next prime is 6261128051663. The reversal of 6261128051661 is 1661508211626.

6261128051661 is a `hidden beast` number, since 6 + 2 + 6 + 1 + 128 + 0 + 516 + 6 + 1 = 666.

It is not a de Polignac number, because 6261128051661 - 2² = 6261128051657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6261128051663) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 53546230 + ... + 53663031.

Almost surely, 2^{6261128051661} is an apocalyptic number.

It is an amenable number.

6261128051661 is a deficient number, since it is larger than the sum of its proper divisors (4531842772403).

6261128051661 is a wasteful number, since it uses less digits than its factorization.

6261128051661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107209383 (or 107209374 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 6261128051661 in words is "six trillion, two hundred sixty-one billion, one hundred twenty-eight million, fifty-one thousand, six hundred sixty-one".