1157665533561 has 40 divisors (see below), whose sum is σ = 1800573354888. Its totient is φ = 740609568000.

The previous prime is 1157665533547. The next prime is 1157665533589. The reversal of 1157665533561 is 1653355667511.

1157665533561 is a `hidden beast` number, since 1 + 1 + 5 + 76 + 6 + 5 + 5 + 3 + 3 + 561 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 183064179600 + 974601353961 = 427860^2 + 987219^2 .

It is not a de Polignac number, because 1157665533561 - 2¹¹ = 1157665531513 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1157665533498 and 1157665533507.

It is not an unprimeable number, because it can be changed into a prime (1157665533961) 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, 2654710 + ... + 3059871.

Almost surely, 2^{1157665533561} is an apocalyptic number.

It is an amenable number.

1157665533561 is a deficient number, since it is larger than the sum of its proper divisors (642907821327).

1157665533561 is an equidigital number, since it uses as much as digits as its factorization.

1157665533561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5714695 (or 5714686 counting only the distinct ones).

The product of its digits is 8505000, while the sum is 54.

The spelling of 1157665533561 in words is "one trillion, one hundred fifty-seven billion, six hundred sixty-five million, five hundred thirty-three thousand, five hundred sixty-one".