1865946961 has 2 divisors, whose sum is σ = 1865946962. Its totient is φ = 1865946960.

The previous prime is 1865946931. The next prime is 1865946989. The reversal of 1865946961 is 1696495681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1089990225 + 775956736 = 33015^2 + 27856^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1865946961 is a prime.

It is a super-2 number, since 2×1865946961² = 6963516122530271042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1865946931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 932973480 + 932973481.

It is an arithmetic number, because the mean of its divisors is an integer number (932973481).

Almost surely, 2^1865946961 is an apocalyptic number.

It is an amenable number.

1865946961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1865946961 is an equidigital number, since it uses as much as digits as its factorization.

1865946961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2799360, while the sum is 55.

The square root of 1865946961 is about 43196.6082117566. The cubic root of 1865946961 is about 1231.1182376938.

The spelling of 1865946961 in words is "one billion, eight hundred sixty-five million, nine hundred forty-six thousand, nine hundred sixty-one".