646103881 has 2 divisors, whose sum is σ = 646103882. Its totient is φ = 646103880.

The previous prime is 646103863. The next prime is 646103893. The reversal of 646103881 is 188301646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 558849600 + 87254281 = 23640^2 + 9341^2 .

It is a cyclic number.

It is not a de Polignac number, because 646103881 - 2⁵ = 646103849 is a prime.

It is a super-2 number, since 2×646103881² = 834900450086524322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 646103881.

It is not a weakly prime, because it can be changed into another prime (646103851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323051940 + 323051941.

It is an arithmetic number, because the mean of its divisors is an integer number (323051941).

Almost surely, 2^646103881 is an apocalyptic number.

It is an amenable number.

646103881 is a deficient number, since it is larger than the sum of its proper divisors (1).

646103881 is an equidigital number, since it uses as much as digits as its factorization.

646103881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 646103881 is about 25418.5735437691. The cubic root of 646103881 is about 864.5048815428.

The spelling of 646103881 in words is "six hundred forty-six million, one hundred three thousand, eight hundred eighty-one".