2180661851 has 2 divisors, whose sum is σ = 2180661852. Its totient is φ = 2180661850.

The previous prime is 2180661823. The next prime is 2180661869. The reversal of 2180661851 is 1581660812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2180661851 - 2¹⁸ = 2180399707 is a prime.

It is a super-2 number, since 2×2180661851² = 9510572216813492402, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2180661151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1090330925 + 1090330926.

It is an arithmetic number, because the mean of its divisors is an integer number (1090330926).

Almost surely, 2^2180661851 is an apocalyptic number.

2180661851 is a deficient number, since it is larger than the sum of its proper divisors (1).

2180661851 is an equidigital number, since it uses as much as digits as its factorization.

2180661851 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23040, while the sum is 38.

The square root of 2180661851 is about 46697.5572273326. The cubic root of 2180661851 is about 1296.7694640832.

The spelling of 2180661851 in words is "two billion, one hundred eighty million, six hundred sixty-one thousand, eight hundred fifty-one".