39198555661 has 2 divisors, whose sum is σ = 39198555662. Its totient is φ = 39198555660.

The previous prime is 39198555659. The next prime is 39198555677. The reversal of 39198555661 is 16655589193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34733776900 + 4464778761 = 186370^2 + 66819^2 .

It is a cyclic number.

It is not a de Polignac number, because 39198555661 - 2¹ = 39198555659 is a prime.

It is a super-3 number, since 3×39198555661³ (a number of 33 digits) contains 333 as substring.

Together with 39198555659, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 39198555596 and 39198555605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39198555061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19599277830 + 19599277831.

It is an arithmetic number, because the mean of its divisors is an integer number (19599277831).

Almost surely, 2^39198555661 is an apocalyptic number.

It is an amenable number.

39198555661 is a deficient number, since it is larger than the sum of its proper divisors (1).

39198555661 is an equidigital number, since it uses as much as digits as its factorization.

39198555661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8748000, while the sum is 58.

The spelling of 39198555661 in words is "thirty-nine billion, one hundred ninety-eight million, five hundred fifty-five thousand, six hundred sixty-one".