191978657356 has 6 divisors (see below), whose sum is σ = 335962650380. Its totient is φ = 95989328676.

The previous prime is 191978657341. The next prime is 191978657393. The reversal of 191978657356 is 653756879191.

191978657356 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 191978657291 and 191978657300.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23997332166 + ... + 23997332173.

Almost surely, 2^191978657356 is an apocalyptic number.

It is an amenable number.

191978657356 is a deficient number, since it is larger than the sum of its proper divisors (143983993024).

191978657356 is a wasteful number, since it uses less digits than its factorization.

191978657356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47994664343 (or 47994664341 counting only the distinct ones).

The product of its digits is 85730400, while the sum is 67.

The spelling of 191978657356 in words is "one hundred ninety-one billion, nine hundred seventy-eight million, six hundred fifty-seven thousand, three hundred fifty-six".