166520406426 has 32 divisors (see below), whose sum is σ = 366319889856. Its totient is φ = 50460726800.

The previous prime is 166520406397. The next prime is 166520406439. The reversal of 166520406426 is 624604025661.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10417785 + ... + 10433756.

It is an arithmetic number, because the mean of its divisors is an integer number (11447496558).

Almost surely, 2^166520406426 is an apocalyptic number.

166520406426 is an abundant number, since it is smaller than the sum of its proper divisors (199799483430).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166520406426 is a wasteful number, since it uses less digits than its factorization.

166520406426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20851579 (or 20851557 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 42.

The spelling of 166520406426 in words is "one hundred sixty-six billion, five hundred twenty million, four hundred six thousand, four hundred twenty-six".