1540680161 has 4 divisors (see below), whose sum is σ = 1569749652. Its totient is φ = 1511610672.

The previous prime is 1540680143. The next prime is 1540680173. The reversal of 1540680161 is 1610860451.

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 836308561 + 704371600 = 28919^2 + 26540^2 .

It is a cyclic number.

It is not a de Polignac number, because 1540680161 - 2¹⁸ = 1540418017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1540680181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14534666 + ... + 14534771.

It is an arithmetic number, because the mean of its divisors is an integer number (392437413).

Almost surely, 2^1540680161 is an apocalyptic number.

It is an amenable number.

1540680161 is a deficient number, since it is larger than the sum of its proper divisors (29069491).

1540680161 is an equidigital number, since it uses as much as digits as its factorization.

1540680161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29069490.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 1540680161 is about 39251.4988376240. The cubic root of 1540680161 is about 1154.9703361259.

The spelling of 1540680161 in words is "one billion, five hundred forty million, six hundred eighty thousand, one hundred sixty-one".