3964453981 has 2 divisors, whose sum is σ = 3964453982. Its totient is φ = 3964453980.

The previous prime is 3964453979. The next prime is 3964453993. The reversal of 3964453981 is 1893544693.

It is a happy number.

3964453981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3382004025 + 582449956 = 58155^2 + 24134^2 .

It is a cyclic number.

It is not a de Polignac number, because 3964453981 - 2¹ = 3964453979 is a prime.

It is a super-2 number, since 2×3964453981² = 31433790734933496722, which contains 22 as substring.

Together with 3964453979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3964454981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1982226990 + 1982226991.

It is an arithmetic number, because the mean of its divisors is an integer number (1982226991).

Almost surely, 2^3964453981 is an apocalyptic number.

It is an amenable number.

3964453981 is a deficient number, since it is larger than the sum of its proper divisors (1).

3964453981 is an equidigital number, since it uses as much as digits as its factorization.

3964453981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2799360, while the sum is 52.

The square root of 3964453981 is about 62963.9101470041. The cubic root of 3964453981 is about 1582.6849052410.

The spelling of 3964453981 in words is "three billion, nine hundred sixty-four million, four hundred fifty-three thousand, nine hundred eighty-one".