1981373963 has 2 divisors, whose sum is σ = 1981373964. Its totient is φ = 1981373962.

The previous prime is 1981373923. The next prime is 1981373969. The reversal of 1981373963 is 3693731891.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1981373963 - 2⁶ = 1981373899 is a prime.

It is a super-3 number, since 3×1981373963³ (a number of 29 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (1981373969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 990686981 + 990686982.

It is an arithmetic number, because the mean of its divisors is an integer number (990686982).

Almost surely, 2^1981373963 is an apocalyptic number.

1981373963 is a deficient number, since it is larger than the sum of its proper divisors (1).

1981373963 is an equidigital number, since it uses as much as digits as its factorization.

1981373963 is an evil number, because the sum of its binary digits is even.

The product of its digits is 734832, while the sum is 50.

The square root of 1981373963 is about 44512.6270062777. The cubic root of 1981373963 is about 1255.9976222368.

The spelling of 1981373963 in words is "one billion, nine hundred eighty-one million, three hundred seventy-three thousand, nine hundred sixty-three".