1686161401 has 4 divisors (see below), whose sum is σ = 1686310900. Its totient is φ = 1686011904.

The previous prime is 1686161383. The next prime is 1686161417. The reversal of 1686161401 is 1041616861.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1041616861 = 3391 ⋅307171.

It can be written as a sum of positive squares in 2 ways, for example, as 1091972025 + 594189376 = 33045^2 + 24376^2 .

It is a cyclic number.

It is not a de Polignac number, because 1686161401 - 2⁵ = 1686161369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1686161431) 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, 56316 + ... + 80893.

It is an arithmetic number, because the mean of its divisors is an integer number (421577725).

Almost surely, 2^1686161401 is an apocalyptic number.

It is an amenable number.

1686161401 is a deficient number, since it is larger than the sum of its proper divisors (149499).

1686161401 is a wasteful number, since it uses less digits than its factorization.

1686161401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149498.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 1686161401 is about 41062.8956723707. The cubic root of 1686161401 is about 1190.2359066708.

The spelling of 1686161401 in words is "one billion, six hundred eighty-six million, one hundred sixty-one thousand, four hundred one".