2061661517 has 4 divisors (see below), whose sum is σ = 2061871740. Its totient is φ = 2061451296.

The previous prime is 2061661513. The next prime is 2061661573. The reversal of 2061661517 is 7151661602.

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 1656001636 + 405659881 = 40694^2 + 20141^2 .

It is a cyclic number.

It is not a de Polignac number, because 2061661517 - 2² = 2061661513 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 (2061661513) 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, 89642 + ... + 110267.

It is an arithmetic number, because the mean of its divisors is an integer number (515467935).

Almost surely, 2^2061661517 is an apocalyptic number.

It is an amenable number.

2061661517 is a deficient number, since it is larger than the sum of its proper divisors (210223).

2061661517 is a wasteful number, since it uses less digits than its factorization.

2061661517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210222.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 2061661517 is about 45405.5229790386. The cubic root of 2061661517 is about 1272.7383238260.

The spelling of 2061661517 in words is "two billion, sixty-one million, six hundred sixty-one thousand, five hundred seventeen".