1976453981 has 2 divisors, whose sum is σ = 1976453982. Its totient is φ = 1976453980.

The previous prime is 1976453977. The next prime is 1976453987. The reversal of 1976453981 is 1893546791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1141764100 + 834689881 = 33790^2 + 28891^2 .

It is an emirp because it is prime and its reverse (1893546791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1976453981 - 2² = 1976453977 is a prime.

It is a super-2 number, since 2×1976453981² = 7812740678021496722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1976453987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 988226990 + 988226991.

It is an arithmetic number, because the mean of its divisors is an integer number (988226991).

Almost surely, 2^1976453981 is an apocalyptic number.

It is an amenable number.

1976453981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1976453981 is an equidigital number, since it uses as much as digits as its factorization.

1976453981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1632960, while the sum is 53.

The square root of 1976453981 is about 44457.3276412337. The cubic root of 1976453981 is about 1254.9571645089.

The spelling of 1976453981 in words is "one billion, nine hundred seventy-six million, four hundred fifty-three thousand, nine hundred eighty-one".