2061666651 has 16 divisors (see below), whose sum is σ = 3000384000. Its totient is φ = 1248829920.

The previous prime is 2061666623. The next prime is 2061666671. The reversal of 2061666651 is 1566661602.

2061666651 = 9670² + 9671² + ... + 9691².

It is not a de Polignac number, because 2061666651 - 2²⁶ = 1994557787 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2061666601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50341 + ... + 81593.

It is an arithmetic number, because the mean of its divisors is an integer number (187524000).

Almost surely, 2^2061666651 is an apocalyptic number.

2061666651 is a deficient number, since it is larger than the sum of its proper divisors (938717349).

2061666651 is a wasteful number, since it uses less digits than its factorization.

2061666651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33266.

The product of its (nonzero) digits is 77760, while the sum is 39.

The square root of 2061666651 is about 45405.5795139760. The cubic root of 2061666651 is about 1272.7393802931.

The spelling of 2061666651 in words is "two billion, sixty-one million, six hundred sixty-six thousand, six hundred fifty-one".