2851641781 has 2 divisors, whose sum is σ = 2851641782. Its totient is φ = 2851641780.

The previous prime is 2851641731. The next prime is 2851641797. The reversal of 2851641781 is 1871461582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2773602225 + 78039556 = 52665^2 + 8834^2 .

It is a cyclic number.

It is not a de Polignac number, because 2851641781 - 2²⁷ = 2717424053 is a prime.

It is a super-2 number, since 2×2851641781² = 16263721694289703922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2851641701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1425820890 + 1425820891.

It is an arithmetic number, because the mean of its divisors is an integer number (1425820891).

Almost surely, 2^2851641781 is an apocalyptic number.

It is an amenable number.

2851641781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2851641781 is an equidigital number, since it uses as much as digits as its factorization.

2851641781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 107520, while the sum is 43.

The square root of 2851641781 is about 53400.7657342102. The cubic root of 2851641781 is about 1418.0721343596.

The spelling of 2851641781 in words is "two billion, eight hundred fifty-one million, six hundred forty-one thousand, seven hundred eighty-one".