2664019681 has 2 divisors, whose sum is σ = 2664019682. Its totient is φ = 2664019680.

The previous prime is 2664019679. The next prime is 2664019703. The reversal of 2664019681 is 1869104662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2170069056 + 493950625 = 46584^2 + 22225^2 .

It is a cyclic number.

It is not a de Polignac number, because 2664019681 - 2¹ = 2664019679 is a prime.

It is a super-2 number, since 2×2664019681² = 14194001721510683522, which contains 22 as substring.

Together with 2664019679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2664019601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1332009840 + 1332009841.

It is an arithmetic number, because the mean of its divisors is an integer number (1332009841).

Almost surely, 2^2664019681 is an apocalyptic number.

It is an amenable number.

2664019681 is a deficient number, since it is larger than the sum of its proper divisors (1).

2664019681 is an equidigital number, since it uses as much as digits as its factorization.

2664019681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 124416, while the sum is 43.

The square root of 2664019681 is about 51614.1422577185. The cubic root of 2664019681 is about 1386.2635674644.

The spelling of 2664019681 in words is "two billion, six hundred sixty-four million, nineteen thousand, six hundred eighty-one".