667952881997 has 2 divisors, whose sum is σ = 667952881998. Its totient is φ = 667952881996.

The previous prime is 667952881951. The next prime is 667952882083. The reversal of 667952881997 is 799188259766.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 436109668996 + 231843213001 = 660386^2 + 481501^2 .

It is a cyclic number.

It is not a de Polignac number, because 667952881997 - 2³² = 663657914701 is a prime.

It is a super-2 number, since 2×667952881997² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667952881597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333976440998 + 333976440999.

It is an arithmetic number, because the mean of its divisors is an integer number (333976440999).

Almost surely, 2^667952881997 is an apocalyptic number.

It is an amenable number.

667952881997 is a deficient number, since it is larger than the sum of its proper divisors (1).

667952881997 is an equidigital number, since it uses as much as digits as its factorization.

667952881997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 823011840, while the sum is 77.

The spelling of 667952881997 in words is "six hundred sixty-seven billion, nine hundred fifty-two million, eight hundred eighty-one thousand, nine hundred ninety-seven".