1951678643 has 2 divisors, whose sum is σ = 1951678644. Its totient is φ = 1951678642.

The previous prime is 1951678621. The next prime is 1951678661. The reversal of 1951678643 is 3468761591.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1951678643 - 2¹⁰ = 1951677619 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1951678591 and 1951678600.

It is not a weakly prime, because it can be changed into another prime (1951674643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 975839321 + 975839322.

It is an arithmetic number, because the mean of its divisors is an integer number (975839322).

Almost surely, 2^1951678643 is an apocalyptic number.

1951678643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1951678643 is an equidigital number, since it uses as much as digits as its factorization.

1951678643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 50.

The square root of 1951678643 is about 44177.8071320884. The cubic root of 1951678643 is about 1249.6913676431.

The spelling of 1951678643 in words is "one billion, nine hundred fifty-one million, six hundred seventy-eight thousand, six hundred forty-three".