209978606057 has 16 divisors (see below), whose sum is σ = 235326347712. Its totient is φ = 185676966720.

The previous prime is 209978606027. The next prime is 209978606063. The reversal of 209978606057 is 750606879902.

209978606057 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 209978606057 - 2⁸ = 209978605801 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 209978605987 and 209978606005.

It is not an unprimeable number, because it can be changed into a prime (209978606017) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 1375178 + ... + 1520220.

It is an arithmetic number, because the mean of its divisors is an integer number (14707896732).

Almost surely, 2^209978606057 is an apocalyptic number.

It is an amenable number.

209978606057 is a deficient number, since it is larger than the sum of its proper divisors (25347741655).

209978606057 is a wasteful number, since it uses less digits than its factorization.

209978606057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148648.

The product of its (nonzero) digits is 11430720, while the sum is 59.

The spelling of 209978606057 in words is "two hundred nine billion, nine hundred seventy-eight million, six hundred six thousand, fifty-seven".