166920209547 has 32 divisors (see below), whose sum is σ = 273981055488. Its totient is φ = 88026310656.

The previous prime is 166920209531. The next prime is 166920209567. The reversal of 166920209547 is 745902029661.

It is not a de Polignac number, because 166920209547 - 2⁴ = 166920209531 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 166920209547.

It is not an unprimeable number, because it can be changed into a prime (166920209507) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1210308 + ... + 1341150.

It is an arithmetic number, because the mean of its divisors is an integer number (8561907984).

Almost surely, 2^166920209547 is an apocalyptic number.

166920209547 is a deficient number, since it is larger than the sum of its proper divisors (107060845941).

166920209547 is a wasteful number, since it uses less digits than its factorization.

166920209547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135539.

The product of its (nonzero) digits is 1632960, while the sum is 51.

The spelling of 166920209547 in words is "one hundred sixty-six billion, nine hundred twenty million, two hundred nine thousand, five hundred forty-seven".