939857672561 has 2 divisors, whose sum is σ = 939857672562. Its totient is φ = 939857672560.

The previous prime is 939857672557. The next prime is 939857672591. The reversal of 939857672561 is 165276758939.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 756823441936 + 183034230625 = 869956^2 + 427825^2 .

It is an emirp because it is prime and its reverse (165276758939) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 939857672561 - 2² = 939857672557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 939857672491 and 939857672500.

It is not a weakly prime, because it can be changed into another prime (939857672591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 469928836280 + 469928836281.

It is an arithmetic number, because the mean of its divisors is an integer number (469928836281).

Almost surely, 2^939857672561 is an apocalyptic number.

It is an amenable number.

939857672561 is a deficient number, since it is larger than the sum of its proper divisors (1).

939857672561 is an equidigital number, since it uses as much as digits as its factorization.

939857672561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 171460800, while the sum is 68.

The spelling of 939857672561 in words is "nine hundred thirty-nine billion, eight hundred fifty-seven million, six hundred seventy-two thousand, five hundred sixty-one".